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Nei sedimenti neritiei del Cretacico superiore dell'Appennino sono presenli dei miliolidi planispirali, involuti, spesso provvisti di stadio svolto. con apertura cribrata ed endoscheletro costituito, nelle logge adulte, da strato basale e da lame. Questi caratteri sono quelli che fino ad ora caratterizzavano il genere Raadshoovenia VAN DEN BOLD. Allo scopo di accertare fino a che punto le forme da me riscontrate differissero da quelle' guatemalteche ho esaminato alcuni esemplari di Raadshoovenia guatemalensis raccolti da VAN DEN BOLD. In essi ho potuto riscontrare dci caratteri interni più complessi di quelli che figurano nella diagnosi generica; questi sono costituiti, nelle logge adulte, oltre che da lame anche da strato basale e da pilastri che, lateralmente, si saldano tra loro e con le lame determinando camerette centrali e marginali. Si è reso perciò opportuno l'emendamento del genere Raadshoovenia e della sua specie tipo R. guatemalellsis. In base alla diagnosi emendata risultano sinonimi del genere di VAN DEN BOLD Cuvillierinella (PAPETTI e TEDESCHI, 1965) e Murciella (FOURCADE, 1966). Le forme da me rinvenute nell'Appennino e che soddisfano alla vecchia diagnosi di Raaclshoovenia sono state attribuite a Scandonea n. gen. la cui specie tipo è Scandonea samnitica n. sp. Si è proposta, inoltre, una diagnosi più comprensiva per ]a famiglia Alveolinidae al fine di poter inserire in essa il genere di VAN DEN BOLD. In questo lavoro ho accennato, in un apposito paragrafo, alla nomenclatura adottata. In particolare, le misure di altezza sono espresse da segmenti perpendicolari all'asse di avvolgimento o all'andamento della spira; per questo motivo altezza del guseio o dei giri sono sinonimi di diametro del guscio e diametro dei giri. Le misure di larghezza sono espresse da segmenti paralleli all'asse di avvolgimento; quelle di lunghezza vengono eseguite parallelamente all'andamento della spira.
Baltic Sea
(1957)
This study treats 76 species, in which 58 species and 14 genera are described as new. The species are arranged in 28 families and 56 genera. The oribatid or cryptostigmatid mites are cosmopolitan group of more than 6500 species relegated to approximate 700 genera and 134 families. The body length of most oribatid species ranges 300-1200 µ. The oribatid mites are darkly coloured and covered with a rigid exoskelecton. The life cycle consists of egg, larva, protonymph, tritonymph, deutonymph and adult. These mites are best known as inhabitants of litter and upper soil strata, their small size and shunning of light caused them to receive little attention for many years. In recently studies of soil fauna, it has been shown that is an economic importance for human, i.e. many species feed on surface plant detritus, and may therefore play a major role in maintaining the fertility of soils; they could become an indicator of soil physical and chemical characters. Some species have also been shown to act as vectors of various tapewonns; they feed almost exclusively on tyroglyphid mites and attack the parasitic hymenopteran, Polynotus zosini; and several species are associated with plant, they have been reported to damage the leaf, the foot and the stem of potato, strawberry, turlip, citrus and mushroom. Systematic studies of these mites are scarcely found in Taiwan. The present paper deals with 76 species, 56 genera in 28 families, among them, 58 species and 14 genera are described as new. The author hopes that this study constitutes an example to show that the wealth of fascinating information could be gained and also hopes that this finding might be useful for elucidating the taxonomy of oribatid mites in Taiwan.
Interaction between species in a marine ecosy stem is described by expressions for food consumption and grazing mortality which are consistent with each other and with the Beverlon and Holt model of the population dynamics ofindividual species. A model of primary production is introduced in order to make possible an account of nutricnt circlliation (as examplified by phosphorus) within and nutrient flow through the system. It is demonstrated in an application to North Sea fishencs that recent changes in total yield can be described in some detail under the terms of the model as a function of fishing mortality alone. The composition of the North Sea fauna in the virgin state is discussed and also the conditions under which total yield could be increased above the 1970 level.
Techniques for collecting, handling, preparing, storing and examining small molluscan specimens
(2007)
Micromolluscs are small-sized molluscs (< 5 mm), and include the great majority of undescribed molluscan taxa. Such species require special collecting, sorting and handling techniques and different storage requirements to those routinely used for larger specimens. Similarly, the preparation of shells, opercula, radulae and animals poses some challenges for scanning electron microscopy (SEM). An overview of experiences with various techniques is presented, both positive and negative. Issues discussed include those relating to storage of dry specimens and interaction of specimens with glass, gelatine and paper products, handling techniques and storage in various fluids. Techniques for cleaning shells for SEM are described and compared, as well as those for radular extraction. The interactions of chemicals used for the dissolution of tissue with calcareous micromolluscs are described. Methods for handling and mounting small radulae for SEM are detailed and brief guides to SEM and light photography are given. An appendix listing details of frequently-used chemicals is provided.
This paper describes the effect of the "Boleslaw" mining and metallurgic complex in Bukowno near Olkusz on the vegetation of the fresh coniferous forest association Vaccinia myrtilli-Pineitum. The increase in concentration of zinc, lead and cadmium in selected plant species under the influence of industrial emission, and the dependence of this increase upon the magnitude of dust fall and site conditions, are analized. The extent of accumulation of heavy metals in plants was assumed to be an indicator of the degree of pressure exerted by the industrial complex. The degradation of fresh coniferous forest was. increasing along with an increase in this pressure. The species composition of the association, and the quantitative relations among species representing various site types underwent considerable changes. In patches extremely degraded, the plant species characteristic of poor sandy grass-lands gained predominance over forest plants.
Several mosquito-borne arboviruses belonging to the genera Alphavirus, Flavivirus, and Bunyavirus have been reported to occur in mosquitoes and to infect humans and other vertebrates in western Europe. These zoonotic viruses circulate in nature either in an Aedes-mammal, Anopheles-mammal, or Culex-bird transmission cycle. Infected humans normally do not contribute to the virus circulation. West Nile virus (Flavivirus) caused an outbreak of fever, malaise, pain in eyes and muscles, and headache and encephalitis in southern France during 1962-1965, and an outbreak of encephalitis with a high case-fatality rate in Romania during 1996. West Nile virus has been isolated from birds, horses, and mosquitoes in Portugal, France, the former Czechoslovakia, and Romania. These data, together with reports of antibodies to West Nile virus in birds, domestic mammals, and humans in several other countries, show virus activity in southern and central Europe. Sindbis virus (Alphavirus) caused outbreaks of fever, rash, and arthralgia in northern Europe during 1981-1982, 1988, and 1995. Two California group viruses (Bunyavirus), Tahyna virus and Inkoo virus, have been identified in western Europe. Tahyna virus causes fever and respiratory symptoms and sometimes also central nervous system involvement. It occurs in most countries of central and southern Europe, and is most common in central Europe. Inkoo virus has not been associated with disease in humans in western Europe although Russian studies indicated that it can cause encephalitis. Inkoo virus occurs in northern Europe, especially in the far north. Batai virus of the Bunyamwera-group (Bunyavirus) occurs in southern, central, and northern Europe, most frequently in central Europe. The antibody prevalence in humans generally is very low, indicating that the potential of this virus as a human pathogen is probably low in Europe. The Lednice virus (Bunyavirus) has been reported only from the former Czechoslovakia and Romania, and apparently is not transmitted to humans. In addition to the six mosquito-borne viruses documented in western Europe, there is serological evidence of infection with a Semliki Forest complex virus (Alphavirus) in central and southern Europe. Although mosquito-borne viruses presently are not considered to be the cause of major health problems in western Europe, the morbidity caused by Sindbis virus, and the morbidity and mortality caused by West Nile virus, merit further studies on the ecology, epidemiology, and medical importance of these viruses. The California group of viruses and a virus of the Semliki Forest complex may be the cause of unrecognized health problems in western Europe. Specific sampling of potential vectors for virus isolation, detailed characterization of virus strains, and the use of fully characterized strains for serological diagnosis will help to elucidate the present and future potential of mosquito-borne viruses as human pathogens in Europe.
(1) a. The mating behavior (including copulation) is described for the first time in the following species: Pardosa modica, P. emertoni, P. saxatilis, P. lapidicina, Lycosa helluo, .L. gulosa, Dolomedes scriptus, Phidippus clarus, P. audax, Philodromus pernix, and Coriarachne versicolor. b. The courtship only is described for the first time in Phidippus purpuratus. c. In Lycosa rabida and Pardosa milvina new data concerning the copulation, and in Schizocosa crassipes new data concerning courtship, are added to what is already available from Montgomery's work. d. In Tibellns oblongus and Xysticus triguttatus new data are added to the accounts of Gerhardt, and of Emerton, respectively. (2) a. On the basis of a large number of observations and experiments with the males of 19 species from 4 families of vagabond spiders, it is pointed out that the senses involved in courtship may vary with the species. b. There is no evidence that a sense of smell is used in sex recognition by any spiders. At least this sense plays no part in initiating courtship activity in the male. c. There is no evidence that Attid males can "recognize" the females by any sense other than sight. At any rate, it appears that the visual stimulus is the only one that suffices to incite courtship in this family. d. In one Lycosid observed, Pardosa emertoni, the courtship behavior is elicited only when the male can both see and touch the female. e. In the Pisaurid, Dolomedes scriptus, the sole stimulus for courtship is the chemoperception by contact of an ether-soluble substance normally covering the cuticle of the female. f. In the Lycosid, Pardosa milvina, the chemoperception by contact of an ether-soluble substance normally covering the cuticle of the female, together with the simultaneous perception of tactile stimuli will elicit courtship. This probably holds for P. saxatilis, Lycosa rabida, Schizocosa crassipes, and perhaps for Pardosa modica. Moreover, the sight of a moving Lycosid of about their own size may, in some cases, be sufficient for these males to start courting. g. In the Lycosids, Pardosa banksi, and probably Lycosn gulosa and L. helluo, only the simultaneous perception of both tactile and tacto-chemical stimuli suffices. Visual stimuli play no part in eliciting courtship. h. The condition in the Thomisids is in all probability similar to that in the preceding group of Lycosids. (3) a. In the case of those species in which contact chemoperception occurs it is shown that perception is not limited to the tarsi. Such stimuli can be perceived on all the segments of the legs as well as on the abdomen. From the known distribution of the slit sense organs it is probable that they are the chemoreceptors involved in courtship.
Naturschutz in Germany
(1936)
Distribution and variation in deer (Genus Odocoileus) of the Pacific Coastal Region of North America
(1936)
1. In investigating a spontaneous epidemic disease of rabbits, a micro-organism was isolated in pure cultures which reproduced the characteristic lesions of the natural disease.
2. The bacteriological characters of this bacillus are described and the impossibility of identifying it with previously recorded organisms justifies its being considered a new species. The name Bacterium monocytogenes is proposed.
3. Animal passage raised "virulence" when the doses were well chosen, and increased virulence accentuated the production of necrotic lesions. Overwhelming doses of culture resulted in lowering of "virulence" by animal passage.
4. Bacterium monocytogenes, in doses less than the M.L.D., produced in the circulating blood of rabbits an extreme monocytosis. The responses of the other white cells. were either transient or inconstant.
5. Repeated doses of the organism became progressively less effective as stimuli to large mononuclear production.
6. The cell content of the thoracic duct did not reflect the high degree of monocytosis in the circulating blood.
7. On intrapleural injection of peptone broth and B. coli, the cells of the resultant exudate were primarily polymorphonuclears, even though the circulating blood showed a high monocytosis. With intrapleural injection of B. monocytogenes, when the blood stream was rich in large mononuclears, a pleural exudate containing 30 per cent of these cells was obtained.
8. Phagocytosis experiments in vitro showed that the large mononuclears, while they phagocyted B. coli indifferently, took up B. monocytogenes with an avidity in all respects equal to that of the polymorphonuclear neutrophiles.
Aside from material collected and annotated during my trip to Ecuador in April and May 1973, mentioned in the frrst part of the present paper (1975), the author has been able to study Aphyllophorales and agarics collected by Dumont and others, deposited at The Botanical Garden in New York. The results are presented in the following pages. A few species from limitrophous regions are added. The first article in this series was published in Beiheft 51 zur Nova Hedwigia, pp. 239-246, 1975.
The study of rich material of Pterophoridae from Siberia and the Russian Far East revealed 96 species to inhabit these regions. 24 of them are reported for the first time from Asian Russia and 11 species and 2 genera (Sibiretta gen. nov. and Septuaginta gen. nov.) are described as new. Furthermore the genus Snellenia gen. nov. is described and isolated from the genus Stenoptilia, and previously unknown females are described for three species.
The morphology of the skeletal portions of the sting apparatus is described and compared in 63 genera of myrmicine ants in order to evaluate its taxonomic potential in this difficult subfamily. The survey covers about half of the myrmicine genera, and an but 3 small tribes (Ochetomyrmecini, Melissotarsini, Stegomyrmicini). Interspecific variation in the apparatus is described in a third of the genera examined. In addition, the sting apparatus of the primitive ponerine ant, Amblyopone pallipes is described for comparison with the primitive myrmicines; and the sting associated glands (poison gland, Dufour's gland) are illustrated for single species of Amblyopone, Basiceros, Monomorium, Aphaenogaster, Crematogasier, and Zacryptocerus.
Über ein cretaceisches Geschiebe mit Rhizocorallium Gläseli n. sp. aus dem Diluvium bei Leipzig
(1913)
The Indian Hill Mynah (Gracula religiosa) was studied in the field in Assam in north-east India. The aims of the study were two-fold: (i) to understand better this bird's exceptional ability in captivity to imitate human speech; and (ii) to provide background understanding to studies of the importance of early auditory experience and of vocal imitation in the development of normal song patterns in birds. First is given a brief description of the distribution, general behaviour, and breeding biology of this arboreal, sexually isomorphic, semi-gregarious species. The remainder of the monograph deals with vocalizations; these were either tape-recorded in the field, or transcribed directly using a written notation developed for the purpose. Any wild adult Mynah of either sex possesses four categories of vocalizations: (i) 'Chip-call'; a loud piercing squeak made in contexts which include alarm. (ii) 'Um-sound'; a soft grunt, acting in close range social contexts, and (like chip-calls) common to all individuals. (iii) 'Whisper-whistles': several soft sounds of types unique to the individual. (iv) 'Calls': several loud noises, of extremely varied patterns. The bulk of the monograph deals with 'calls', as defined thus. Calls were compared quantitatively with one another by a method developed which measured the degree of overlap of one sonogram with a tracing of a second sonogram. Both by this method and by ear, calls were divided into discrete types, without intermediates. Birds of either sex have a repertoire of usually between five and twelve such call types, some of which are produced much more commonly than others. Repertoires tend to be larger in birds which call more frequently, or which have mates with large repertoires. The repertoire of a given bird stays largely constant from year to year in size. composition, and proportions. No bird shares any of its call types with its mate, but it shares several of them with near neighbours of the same sex. There is a progressive change of dialect with distance, such that birds nesting more than about 14 km apart have no call types in common. No general characteristics of call structure could be found which were indicative of the sex of the caller, but in a known locality the call type made immediately reveals the sex of the bird producing it. Call types are learnt by selective imitation of neighbouring individuals during a young bird's first several months. A call type common in the repertoire of one bird tends also to be common in the repertoire of a neighbour, except at the edge of the limited range of that call type. Which particular call type a calling bird selects from among those in its repertoire is discussed. Few call types could be related to non-auditory contexts. A bird is likely to repeat the call type last made, and also tends to standardize the order in which it produces its different call types; this standard order tends to be the same as that of its neighbours. A birdtends also to reply at once and to standardize the call type it makes in immediate reply to a particular call type of its mate; again, neighbouring pairs of birds tend to use the same standardized call and reply types. The length of the interval between a particular call and its reply tends to be constant in a given pair of birds, and approximately the same in neighbouring pairs. These are all further aspects of extensive but selective vocal imitation by Mynahs of adult birds; other species are not imitated. Information on calling when in contact with other pairs came mainly from playback experiments, when single calls were presented to nesting pairs of Mynahs. Response strength was measured by the incidence of flight, number of subsequent vocalizations, latency of response, and proportion of playbacks ignored. When presented with playbacks of calls of familiar types (of neighbours) and of unknown types (of strangers), birds responded more strongly to the familiar than to the unknown call types. They did, however, respond somewhat to the unknown call types, which were of patterns never previously heard by them, presumably recognizing these as being Mynah calls by their sound quality. Mynahs responded as strongly to playbacks of neighbours' calls which were not in their own repertoire as to playbacks of neighbours' calls which were. A bird tends to match at once the call last heard (either from a tape recorder or from a wild neighbour), itself producing the same call type at once, if it possesses it in its own repertoire. That call type, and others associated with it, also occurs more frequently thereafter. Thus calls heard affect calls made, and vice-versa since other individuals nearby behave similarly. A change of nearest neighbours in successive years was shown to affect one pair's repertoire proportions. Further playback experiments showed that Mynahs were able to distinguish between a single call made by their neighbours and a single call of the same call type made by their mates. Small but consistent differences were found in the sonograms of such calls of the same type made by different birds. The structure of a single call type may change gradually with distance. The development of vocalizations with age is briefly described. In the final discussion sections, the ways in which, and the extent to which, Mynahs are able to determine the species, home locality, sex and individual identity of other Mynahs are outlined. There follow consideration, and comparison with other species: (i) of various aspects of repertoires; (ii) of the distribution of call types among different individuals; (iii) of the dynamic aspects of calling, and a scheme is proposed which accounts for the selection for utterance of a particular call type from the repertoire; and (iv) of the organization and coordination of calling. The lack of imitation of other species in the wild is discussed, and contrasted with the several ways in which wild Mynahs imitate one another in various aspects of their calling.
In einem ausführlichen Verzeichnis sind alle bayerischen Fundorte mit näheren Angaben zusammengestellt. Darüber hinaus soll ein Überblick über die Verbreitungsverhältnisse der Art in Europa und auf der Erde vermittelt werden. Die bis heute bekannte Verbreitung tn Europa läßt den Schluß zu, daß Octodiceras fontanum mit großer Wahrscheinlichkeit noch an vielen Stellen aufzufinden sein wird. Die bryosoziologischen Verhältnisse des Octodiceratetum werden durch soziologische Aufnahmen aus Ostbayern belegt. Der Vergleich mit Literaturangaben aus anderen europäischen Gebieten ergibt eine recht einheitliche Ausbildung dieser Wassermoosgesellschaft. Außerdem wird versucht, die ökologischen Verhältnisse des Octodiceratetum zu erfassen. Die entsprechenden Ausführungen müssen sich dabei v.a. auf die Untersuchungen in Ostbayern stützen, da aus anderen europäischen Gebieten nur wenige, vergleichbare Angaben vorliegen. Es wird daher in erster Linie angestrebt, vergleichbare Werte für zukünftige Untersuchungen in anderen Gebieten zu liefern. Die derzeitige Kenntnis des ökologischen Faktorenkomplexes für Octodiceras fontanum läßt noch manche Frage offen. Das Literaturverzeichnis enthält den Großteil der Veröffentlichungen über europäische Octodiceras-Standorte. Es wurden bewußt nur die Arbeiten aufgenommen, die auch eingesehen werden konnten.
Results from a comparative anatomical study of the mesosomal skeleton of Chalcidoidea are presented. External and internal features are described and illustrated for 39 chalcidoid taxa, representing 16 families and 29 subfamilies. This is the most comprehensive morphological study ever conducted for the superfamily. The mesosoma was dissected, macerated and investigated using scanning electron microscopy. The mesothorax and metathorax contributed most of the phylogenetically relevant information. The metafurca is highly variable within Chalcidoidea but seems to be relatively constant at the subfamily level. One hundred and fifty-four morphological characters were scored and analysed cladistically. Outgroup species were chosen from six apocritan superfamilies: Stephanoidea, Ceraphronoidea, Cynipoidea, Platygastroidea, Proctotrupoidea and Mymarommatoidea. Some previously suggested chalcidoid relationships were retrieved: (1) Pteromalidae: Pteromalinae + Miscogasterinae + Panstenoninae; (2) Perilampidae + Eucharitidae; (3) Chalcididae + Leucospidae + Eurytomidae; (4) Eulophidae: Eulophinae + Tetrastichinae + Entedoninae; and (5) Eupelmidae + Encyrtidae, Mymarommatoidea renders Chalcidoidea paraphyletic in our analyses; however, the taxon sample is too restricted to provide a robust hypothesis. Three previously unreported putative autapomorphies of Chalcidoidea were revealed: (1) presence of an exposed, triangular or diamond-shaped prosternum; (2) presence of a percurrent mesopleural sulcus anteriorly terminating in the acropleuron; and (3) presence of paired metapectal plates lateral to the metafurca.
Lepidoptera phylogeny and systematics : the state of inventorying moth and butterfly diversity
(2007)
The currently recognized robust support for the monophyly of the Lepidoptera (and the superorder Amphiesmenoptera comprising Lepidoptera + Trichoptera) is outlined, and the phylogeny of the principal lineages within the order is reviewed succinctly. The state of the taxonomic inventory of Lepidoptera is discussed separately for ‘micro-moths’, ‘macro-moths’ and butterflies, three assemblages on which work has followed historically somewhat different paths. While currently there are about 160,000 described species of Lepidoptera, the total number of extant species is estimated to be around half a million. On average, just over one thousand new species of Lepidoptera have been described annually in recent years. Allowing for the new synonyms simultaneously established, the net increase in species numbers still exceeds 800/year. Most of the additions are foreseeable in the micro-moth grade, but even for butterflies ca 100 species are added annually. Examples of particularly interesting new high-rank taxa that have been described (or whose significance has become realized) since the middle of the 20th century include the non-glossatan lineages represented by Agathiphaga and Heterobathmia and the heteroneuran families Andesianidae, Palaephatidae, Hedylidae and Micronoctuidae. Some thoughts on how present and future systematic lepidopterology might be prioritised are presented.
On the occurence of bats (Chiroptera) in South Tyrol (2): Vespertilionidae Since 1988 the author has been collecting and recording bat observations in South Tyrol. From 1990 to 1991 and from 1995 to 1997, in two different studies, he carried on a survey on the presence, the frequency and the horizontal and vertical dispersal of the various species of bats. The first task was on one hand to search the attics and steeples of about 700 churches and chapels; and, on the other hand, to answer the numerous calls telling of the presence of bats in private houses, to capture bats for a check-up and to inform people about European bats beeing harmless for humans, animals and houses. There is good evidence of 23 species of bats in South Tyrol since 1988 and of the reproduction of 18 of them, as well as there are single discoveries of three further species, and finally summer colonies of two species. As there is no certified evidence of the presence of Pipistrellus pygmaeus and of Plecotus alpinus they have not been included in this record. The data-base already provides a good idea of the presence and frequency of bat-species. Species which are frequent in Central Europe have been found almost everywhere in South Tyrol (e.g. Pipistrellus pipistrellus, Plecotus sp.), some of them in several colonies with a considerable number of individuals. The Etsch/ Adige Valley as far up as Meran/Merano - due to its mild climate - makes home for a few Mediterrean species. The few possibilities we got from scientific pubblications to make a comparison with former times let suppose that the bat occurences have diminued only in a few species. The reasons are to search mainly in the diminued offer of food.
The factors responsible for determining the host-plants and feeding sites of aphids, and the various probing activities (the role of the labium, stylet insertion, surface saliva deposition, the behaviour of the aphid, virus transmission) are examined. There is a brief review of stylet structure and movement and the possible sensory nature of these organs, followed by a detailed review of the characteristics of aphid stylet paths in plant tissues. The penetration of epidermis and vascular tissues is treated separately while that within the intermediate tissues is covered in relation to leaves and stems, roots, trees, galls and excised tissue as well as in separate sections on Aphis fabae Scopoli and Myzus persicae (Sulzer). Stylet destinations and behaviour in the sieve tubes are discussed together with general features such as rate and depth of penetration, guidance to the feeding site, effects of tissue hardness and stylet withdrawal. The ingestion rate of plant sap is reviewed and its constitution and importance examined together with the significance of artificial diets. The salivary secretions including sheaths and tracks, their functions and their role in the transference of material between aphid and host are dealt with. The nature of the physical and internal damage resulting from aphid feeding is briefly covered, and also some plant-insect interrelations. The aphid species whose stylets have been examined in plant tissue are listed.
The objects of this work were to reinvestigate and extend the results announced in a brief note published in 1925 (Murray and Huxley, 1925a). In this paper it was concluded that isolated fragments of the limb buds of the fourday chick are able to self-differentiate when Iiving as grafts on the chorio-allantoic membrane of older chicks; that the bud of the four-day chick is a mosaic; it was hinted that each of the morphological regions of the limb (femur, tibia-fibula, etc.) is represented by a Single piece of the mosaic; that no regeneration or regulation occurs in fragments of the bud, except that it was concluded that if a grafted fragment contains only part of a piece of the mosaic, that part could so regulate its future development as to form the complete morphological region of which it was originally a part, so that a fragment of the bud which contains part only of the region Which would normally form femur will, when growing as a graft, form a complete femur. It will be seen that the results of the present work uphold and confirm the tentative conclusions previously advanced, except in regard to the last point (regulation). A considerable amonnt of further information has also been obtained bearing on tile factors concerned in the development of the form of bones and joints.
The taxonomy, diversity, and distribution of the aquatic insect order Trichoptera, caddisflies, are reviewed. The order is among the most important and diverse of all aquatic taxa. Larvae are vital participants in aquatic food webs and their presence and relative abundance are used in the biological assessment and monitoring of water quality. The species described by Linnaeus are listed. The morphology of all life history stages (adults, larvae, and pupae) is diagnosed and major features of the anatomy are illustrated. Major components of life history and biology are summarized. A discussion of phylogenetic studies within the order is presented, including higher classification of the suborders and superfamilies, based on recent literature. Synopses of each of 45 families are presented, including the taxonomic history of the family, a list of all known genera in each family, their general distribution and relative species diversity, and a short overview of family-level biological features. The order contains 600 genera, and approximately 13,000 species.
A multi-part theorem is presented concerning the morphogenesis of high-symmetry structures made of three-dimensional morphological units (MU's) free to move on the surface of a sphere. All parts of each MU interact non-specifically with the remainder of the structure, via an isotropic function of distance. Summing all interactions gives a net figure of merit, X, that depends upon MU positions and orientations. The structure evolves via gradient dynamics, each MU moving down the local gradient of I. The analysis is reresented with generality in Fourier space, which eases the expression of symmetry. Structures near symmetry, but far from a local minimum of I, are analyzed. For each, a symmetrical configuration can be found, for which X is an extremum with respect to symmetry-breaking perturbations. Under gradient dynamics, a quadratic measure of such deviations from symmetry decreases monotonically, anywhere in the large basin of attraction of a local minimum. Thus: high symmetry is an attractor. Application is made to icosahedral virus capsids. The Symmetrization Theorem shows that a stable capsid, maintained by non-specific interactions among its capsomeres, could arise generically in a "bottom-up" process. For animated evolutions that selfassemble into high symmetry, visit http://www.albany.edu/~cmarzec/
Comparing the modern level in the biology of gastrointestinal stem cells with that achieved in the hemopoietic stem cell studies, we can say, using Till's expression (1982), that at present the "morphological phase" in the investigations of the former is continuing. Still urgent is the problem of morphological verification of presumable stem cells in colonic crypts and gastric glands. Also important is to clarify the ways of renewal of the well-differentiated but low proliferating activity endocrine cells, the chief cells of the fundic glands, and the cells of Brunner's glands. Further studies of interaction between epithelial and stromal cells are needed. The knowledge of relationships between stem cells and their differentiated "neighbors" in the niches, as well as of peculiarities of contacts between epithelial cells proper and of the cells with the basement membrane is of major importance. It is also necessary to clarify the mechanisms of the stem cells "anchoring" as well as of the disturbances of this important property during carcinogenesis. Briefly summarized below are the most essential, in our opinion, directions of the study of stem cells; some of these have already been started, whereas others can only be predicted. 1. The isolation from normal tissues of the fractions of intact cells enriched with the stem cells, with their subsequent culture. 2. The clarification of the factors governing the regulation of renewal of stem cells: specific stimulators and inhibitors of proliferation; and characterization of the receptor apparatus of stem cells, particularly for the enteropancreatic hormones. 3. The antigenic characteristic of stem cells. 4. The study of molecular peculiarities of DNA replication of clonogenic cells. 5. The molecular aspects of commitment and differentiation of stem cells. 6. The quantitative and qualitative characteristics of stem cells in the process of carcinogenesis. 7. The qualitative evaluation of the dynamics of formation and disappearance of carcinogenic DNA adducts in stem cells. 8. The clarification of interspecies features of stem cells as well as of their morphogenetic potentialities in onto- and phylogenesis. 9. The characterization of metaplastic changes in stem cells.
The present paper is a continuation of "The Birds of the Galapagos Islands, with Observations all the Birds of Clipperton and Cocos Islands (Columbiformes to Pelecaniformes)". The collection of land bird skins brought back by the Expedition numbers 5,916, exclusive of the Galapagos Dove. The writer lacks the time to study this large number of specimens and therefore deems it advisable to publish his field notes without further delay. In addition to the skins, considerable collections of eggs, nests, and birds and stomachs in alcohol were macle. These also await investigation. The land birds of Cocos Island, Costa Rica, and of the Galapagos Islands are treated in the present connection, with the exception of the Galapagos Dove already considered in the earlier paper. The sequence and nomenclature of species in both papers is that of Sharpe's "Hand-list of the Genera and Species of Birds." As the species of the genera Geospiza and Camarhynchus demand a thorough revision with all available material at hand, the writer uses provisionally, with a few changes, the specific names as defined by Messrs. Rothschild and Hartert and Messrs. Snodgrass and Heller. Wherever the writer fails to recognize a species admitted by these authors, the rejected name is placed in a. selected synonymy. The localities listed for each species also include those mentioned by Messrs. Salvin, Ridgway, Rothschild and Hartert, and Snodgrass and Heller. For a full, description of the botanical regions or zones (dry or arid, moist or humid, and grassy, in order from seashore to mountain top) mentioned in this paper, the reader should refer to Mr. Alban Stewart's paper "A Botanical Survey of the Galapagos Islands."
This paper is a general review of the problem of clutch-size in birds. It grew out of a search through the literature to see to what extent clutch-size trends found in the Robin, Erithaau8 rebecula, might apply generally. Part I. describes those types of clutch-size variation found within any species, Part II. provides a general discussion of the factors involved. In Part IlI, which follows separately later, some of the differences between different species of birds will be considered. Examples are taken mainly from European birds, hence this review is in some ways supplementary to that on African birds by Moreau (1944), to which the present study owes a considerable debt.
On Urnatella gracilis
(1893)
Evidence from archaeological fish bone assemblages from the southern North Sea region of Europe is used to illuminate fishing, fish consumption and fish trade from the 1st to the 16th century AD. The fish species represented in the material indicate a very strong influence from the local fish fauna at almost all sites. The species and size of the fish indicate that several fishing methods have been employed throughout the period studied, including nets, hooks and weirs. A chronological development in fishing, for example, a tendency towards more sea-going fishing, is reflected in the fish bone assemblages in some countlres. Evidence from fishing in the Baltic region from the 5th century BC to the 16th century AD is included in the discussion. Indications of fish trade include bones of exotic species (for instance, matinc species at inland sites) and an unbalanced representation of skeletal clements (trade with decapitated stockfish or gillless hering). Of particular interest are assemblages which indicate a fish industry, for instance, large-scale processing (removal of gills) of herring in 13th century Denmark.