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The primary subdivisions of the brain (telencephalon, diencephalon, mesencephalon, metencephalon, and myelencephalon) have similar relations and comparable functions in all vertebrates. Accordingly, the landmarksthat define their boundaries can be regarded as reliable for following their development. On the basis of a more complete series of well preserved embryos than has been available hitherto, we present evidence that the subdivisions of the adult brain can be traced back to neural-fold stages in which a series of growth centers can be recognized, differing from one another in form, size, and relations. The possibility of following the constrictions between the various subdivisions throughout development has been doubted by some, notably Hochstetter (1919). At present we are convinced that they can be distinguished if certain criteria are followed. These are: (a) constrictions involve the neural tube as a whole; (b) constrictions do not give rise primarily to any neural centers; (c) constrictions change in relative length and width, and in certain stages they become inconspicuous in models. The anatomical descriptions of progressive stages of development have important practical implications. It is known, for example, that congenital malformations of the central nervous system in man are common and that they are responsible for a substantial portion of fetal wastage as well as infant mortality and morbidity. In certain patients comprehensive clinical studies may indicate the underlying abnormality, such as dysraphism, arhinencephaly, hypoplasia of the cerebellum. or absence of the corpus callosum. In addition, anatomical examination of the affected brains may reveal in detail such abnormalities as lyssencephaly, polymicrogyria, or other cortical dysgeneses. These very complex cerebral malformations can only be understood and unraveled in the light of normal development. An investigation of early development of the brain must necessarily begin with a stage in which the major landmarks of the adult brain can be readily identified.As progressively younger stages are analyzed certain landmarks can no longer be recognized, although others persist at least to the third week of gestation. We believe that the evidence on which this study is based can be followed more satisfactorily in this inverted sequence, and the detailed description is so presented. It is followed by a summary of the sequence of events written in the conventional manner, as far as the eighth week of gestation.
A recently completed field survey of springs throughout the Great Basin yielded collections of hydrobiid snails from more than 500 sites, and revealed a wealth of undescribed diversity of these small gastropods. In this, the first or a two-part taxonomic series treating this material, 58 new species of Pyrgulopsis Call & Pilsbry, 1886, are described; and new records are provided for 10 previously described members of this genus. Assignment of these novelties to Pyrgulopsis is done with the acknowledgement that this large genus, as currently constituted, is probably not monophyletic, but a more refined classiffcation of these snails reflecting evolutionary relationships must await preparation of a phylogenetic analysis, which is beyond the scope of this work. Pyrgulopsis occur in a variety of spring-fed water bodies in the Great Basin, including brackish and/or thermal habitats. Although a few species are widespread in the region, local endemism is prevalent lind 22 of the new species are known only from single localities. Several areas contain concentrations of locally endemic snails which may represent species flocks, notably Duckwater Valley (seven species) and southern Steptoe Valley (five species). This fauna is hugely distributed in an allopatric fashion, although a few springs harbor two or three species. Most of the springs inhabited by hydlrobiids in the region are small, fishless, and have been ignored by state and federal land management agencies. However, many of these sites are degraded by livestock grazing, water withdrawal, anti other activities and will require protection in order to conserve snails and other native aquatic biota. Two of the novellies described herein have become extinct during the past two decades.
This second and final part of a taxonomic treatment of hydrobiid snails of the Great Basin region in the western United States (based principally on material collected during a recently completed field survey) focuses on fauna other than the genus Pyrgulopsis. A new genus of small amnieoline snails, Colligyrlls, is proposed for Hydroia greggi Pilsbry, 1935, together with a new species from the Harney Lake basin of Oregon. This group is strongly differentiated from other amnicolines by a unique female genitalic groundplan. New records are provided for three species of Fluminicola, and two new congeners are described from the northwest Great Basin, both of which had previously been confused with F. turbiniformis (Tryon, 1865). A new genus of cochliopine snails, Eremopyrgus, is erected for a new species from Steptoe Valley, Nevada. Eremopyrgus is distinguished from other cochliopines by unique aspects of its glandular penial lobes and other genitalic features. New records are provided for two species of Tyronia, and a new congener is described from thermal springs in central Nevada. Several new records of Pristincola hemphilli (Pilsbry, 1890) from the extreme northwest Great Basin are provided
The present catalogue is an attempt to bring together the genera and species of Trematoda currently known to parasitize Chiroptera Blumenbach, 1774, throughout their world distribution, as published in various journals. Since many of these are difficult to obtain for consultation, it is hoped that this catalogue may be of some utility in facilitating the work of helminthologists working with trematodes from bats.
Die 4. Fassung der Roten Liste der Brutvögel Deutschlands wurde durch das "Nationale Gremium Rote Liste Vögel" erarbeitet, in dem die wissenschaftlichen Institutionen der Ornithologie und Avifaunistik in Deutschland vertreten sind. Die Rote Liste ersetzt die 3. Fassung aus dem Jahr 2002 (BAUER et al. 2002); sie wurde erstmalig nach dem für alle Tier- und Pflanzenartengruppen sowie den Pilzen in Deutschland entwickelten Kriterienschema (5. LUDWIG et al. 2007) erarbeitet. Somit wird ein direkter Vergleich der Gefährdungssituation zwischen diesen Gruppen ermöglicht. Bestandsgröße, kurzfristiger (25 Jahre) und langfristiger (50-150 Jahre) Bestandstrend sind die wichtigsten Parameter zur Gefahrdungseinstufung der einzelnen Arten. Zusätzlich wurde jeweils die Wirksamkeit von Risikofaktoren artspezifisch identifiziert und berücksichtigt. Alle Einstufungen werden transparent vorgenommen und in der Anhangsliste publiziert. Der Dachverband Deutscher Avifaunisten (DDA) hat zur Erstellung der Datengrundlagen mit Stand 2005 für die Gefahrdungseinstufung ein neues Abfrageschema entwickelt, in dem die relevanten Informationen aus den nationalen Vogelmonitoring-Programmen aufgearbeitet und als Hintergrunddaten für die Einschätzungen von Bestandstrend und -größe auf Landesebene bereitgestellt wurden. Dadurch gewinnen die Einstufungen an Verlässlichkeit und Nachvollziehbarkeit. Der langfristige Trend wurde vom "Nationalen Gremium Rote Liste Vogel" ermittelt. Vor der Einstufung der Brutvogelarten wurde je Art eine Statuszuordnung vorgenommen, von denen nur die regelmäßig brütenden einheimischen Arten den weiteren Weg der Rote Liste-Erstellung durchlaufen. In der Roten Liste 2007 werden insgesamt 260 regelmäßige einheimische Brutvogelarten in Deutschland berücksichtigt, 25 weitere Arten brüteten nur unregelmäßig ('vermehrungsgäste': Status II), zudem wurden 29 Neozoen-Arten ermittelt (Status III), von denen 20 regelmäßig brüten. Dies ergibt zusammen 314 Arten, die höchste Zahl an Brutvogelarten, die je für eine Rote Liste zu Grunde gelegt wurde. Insgesamt befinden sich 110 regelmäßige Brutvogelarten in den Kategorien der Roten Liste 2007 (0 = ausgestorben, 1 = vom Aussterben bedroht, 2 :: stark gefährdet, 3 :: gefährdet und R = extrem selten), das entspricht 42,3 % der Arten, was einer minimal geringeren Gefahrdungsquote gegenüber der Vorgängerliste entspricht. Erfreulich ist, dass mit dem Bruchwasserläufer und dem Steinrötel zwei ehemals in Deutschland ausgestorbene Arten zwischen 2000 und 2005 wieder regelmäßig gebrütet haben. Dem entgegen ist mit der Blauracke eine weitere Art ausgestorben. Schwarzstorch, Wanderfalke, Seeadler und Uhu sind hier erstmals seit der ersten deutschen Roten Liste 1971 nicht mehr aufgeführt - ein Erfolg jahrzehntelanger direkter Schutzmaßnahmen der ehrenamtlichen und amtlichen Vogelschützer und gleichzeitig ein Beweis, dass sich Vogelschutz bei stark gefährdeten Arten lohnen kann. Andererseits sind mit Schreiadler, Zwergseeschwalbe oder Großem Brachvogel Alien in die höchste Gefährdungskategorie eingestuft worden, die zwar auch im Fokus des Vogelschutzes standen und stehen, bei denen aber bislang Maßnahmen nicht ausreichend erfolgreich umgesetzt werden konnten. Gerade die Kategorie "vom Aussterben bedroht" umfasst mit nunmehr 30 Arten den höchsten Wert seit Erscheinen der gesamtdeutschen Roten Liste. Der Analyse der aktuellen deutschen Brutvogelfauna zufolge sind die Boden brütenden Vogelarten, Großinsektenfresser und Langstreckenzieher am stärksten von Gefährdungen betroffen. Vogelgruppen mit einem hohen Anteil gefährdeter Arten sind demzufolge Hühnervögel, Rallen, Limikolen und Würger, während Eulen und Schnäpperverwandte derzeit vergleichsweise wenig gefährdet sind. Zudem erfolgt deutschlandweit ein weiteres Ausdünnen der typischen Vögel in der Normallandschaft, was sich vor allem in den Trendanalysen manifestiert, aber in der Roten Liste noch nicht sehr stark zum Ausdruck kommt. Die Nutzungsintensivierungen von Land- und Forstwirtschaft in jüngster Zeit geben hier großen Anlass zur Sorge in diesen Großlebensräumen. Diese Rote Liste stellt erneut ein kritisches Zeugnis über den Zustand der deutschen Vogelwelt aus. Aufgrund der in jüngster Zeit stark ausgeweiteten Monitoringprogramme wird es in Deutschland zukünftig noch besser möglich sein, die Gefahrdung aufzuzeigen. Um den dauerhaften Rückgang der Vogelbestände zu stoppen oder wenigstens zu verlangsamen, müssen die wirksamen Gefahrdungsfaktoren reduziert und minimiert werden. Dem gezielten Vogelartenschutz stellen sich dabei folgende vordringliche Aufgaben: Erhaltung der offenen Kulturlandschaft, Erhaltung strukturreicher Walder, Erhaltung nährstoffarmer Lebensräume, Sicherung der Schutzgebiete - insbesondere Natura 2000, Stärkung der internationalen Zusammenarbeit im Vogelschutz, Reduktion der Populationsverluste durch Unfälle und menschliche Verfolgung sowie Förderung des vogelkundlichen Nachwuchses.
The genus Maculinea van Eecke, 1915 (Lepidoptera: Lycaenidae) from the East Palaearctic Region
(1994)
We revise the classification of taxa belonging to the genus Maculinea from the East Palaearctic Region. In this region, in addition to the well-known three species: M. arion (Linnaeus, 1758), M. ationides (Staudinger, 1887) and M. teleius (Bergstriisser, [1779] 1778-1780), two additional species occur: M. alcon ([Denis & Schiffermiiller], 1775) (upper and middle Amur River, Primor'e, China Northeast/Manchuria and North Korea) and M. kurentzovi sp. nov. (upper and middle Amur River, Primor'e, China Northeast and North Korea). Lycaena kondakovi (Kurentzov, 1970) described from Primor'e is a composite species: the lectotype if' designated here represents an East-Asian subspecies of M. alcon, but its single paralectotype is a female to be assigned to M. kurentzovi sp. nov. Only limited numbers of specimens have been known with M. alcon kondakovi from lowlands of "Far-Eastern" Russia and China Northeast, but in North Korea we found a conspicuous allied taxon arirang nov. (female unknown), which we treat here as a highland subspecies of M. alcon but which may actually represent a good species. Of kurentzovi, we have found a series of specimens which have so far been mostly confused with M. teleius in various collections. We treat Glaucopsyche xiaheana Murayama, 1991 from western Gansu as a subspecies of M. arion along with other subspecies from the central and western parts of China: M. adon philidor (Fruhstorfer, 1915) from the east end of the Qilian Range as well as Mongolia, the type locality, and M. arion inferna nom. nov., a replacement name for Lycaena talsienluica (OberthUr, 1910) (praeoccupied) from Tibet, Sichuan and Qinghai. Because of the similarity of male genitalia and existence of intermediate forms, we regard M. sinalcon Murayama, 1992 described from Qinghai as a subspecies of M. teleius despite a few significant characteristics of the holotype. East continental Asia may be regarded as the headquarter of the genus Maculinea.
Glyptostrobus Endlicher is well represented in early Early Cretaceous to Pleistocene deposits in the middle to high latitudes of North America and Eurasia. Although the taxonomy and nomenclature of the genus is complicated, the fossil record indicates Glyptostrobus was represented by a small number of species. The genus first appears in Aptian age deposits from western Canada and Greenland, and achieved a wide distribution early in its evolutionary history. Exchange of Glyptostrobus between Asia and North America occurred across the Spitsbergen and Beringian corridors, which were functional about 110 and 100 million years ago, respectively The Late Cretaceous fossil record of Glyptostrobus shows that the genus had spread into Russia, China and the shores of the Turgai Strait. By the early Tertiary, Glyptostrobus was a prominent constituent of the polar broad-leaved deciduous forests. Paleocene age deposits across western Canada and the United States indicate the genus was present in great abundance in the lowland warm temperate and subtropical forests east of the Rocky Mountains. The broad distribution in North America and Russia during the Paleocene and Eocene indicates that Glyptostrobus grew and reproduced under a diverse range of climatic and environmental conditions, including the cold and unique lighting conditions of the polar latitudes. The presence of Glyptostrobus in Europe indicates the North Atlantic land bridges that extended between North America and Eurasia (Fennoscandia) and Europe during the early Tertiary were used. In Europe, extensive Glyptostrobus dominated swan1ps occupied the Central European Depression during the late Tertiary. Increasing global aridity and cooling, as well as landscape stabilization together with increasing competition for resources and habitat by representatives of the Pinaceae, seem to have forced the genus out of North America, Europe and most of Asia during the Miocene and Pliocene. In Japan, Glyptostrobus persisted until the early Pleistocene. After the early Pleistocene extinction in Japan, Glyptostrobus reappeared in southeastern China. Details of the taxonomic and biogeographic history of Glyptostrobus are examined.
The regular or obligate aphytophagy of certain lycaenid butterflies (Lepidoptera) is discussed within the framework of the most recent general classification of the family. A summary survey of all Lycaenidae known to be aphytophagous is presented, together with a brief account of cannibalism and other opportunistic aphytophagy exhibited by normally phytophagous butterflies. The range of food sources (plants, animals, excretions and regurgitations) exploited by lycaenids is reviewed with emphasis falling on the ecology of myrmecophilous early stages and the significance of their ant-related adaptations. Adult feeding and oviposition behaviour reveal further associations with ants. Specificity oflycaenid/ant relationships and the possible biological effects ofaphytophagy on the Lycaenidae are discussed. Finally, speculations concerning the evolution of aphytophagy by these bulterflies are critically presented.
Epilabidocera amphitrites is one of the most common copepods in the deep waters adjacent to Friday Harbor and shows characteristic swarming behavior in the surface film of the water from later spring through early summer. That the swarms are composed mainly, up to 99 %, of adult males appears to be due to difference in phototaxis to a weak light. This species, at least in copepodid stages, is omnivorous, but seems to prefer an animal diet rather than diatoms. Reproduction takes place continuously from early spring through autumn. The external anatomy of both the female and male has been described in detail. The cuticle forming the arthrodial membrane and the lining of the esophagus, hindgut, and hypostomal and labral troughs appears to be of the same nature throughout, consisting of a single stratum. The cuticle on the general body surface, however, consists of two main strata. The endoskeletal structures consist of two categories, the endoskeleton proper and the endoskeletal tendons. The former involves apodemes and apophyses. Of these the major ones are described in detail. The latter consist of two median tendinous endosternites in the « head », four pairs of ventral intersegmental thoracic tendons, and a pair of dorsal longitudinal tendons in the metasome. The endosternites are well developed, serving as origins for dilators to the atrium oris and esophagus and also for a number of extrinsic muscles to the head appendages. The skeletomusculature may be divided into longitudinal trunk and limb muscles. The paired dorsal and ventral longitudinal trunk muscles in the metasome extend, respectively, from the levels of the cervical groove and the post-maxillulary apodeme to the end of the metasome. The longitudinal trunk muscles in the urosome origate at the anterior end and run most of its length. They are arranged as paired dorsal and ventral groups and a pair of lateral muscles. The extrinsic limb muscles are described in detail. They originate either from the lateral to dorsal exoskeleton or from the endosternites. The digestive tract starts with the atrium oris in the oral cone, followed by the mouth proper, esophagus, midgut, and finally by the hindgut which opens as the anus at the end of the urosome. The oral cone consisting of the three lobed labrum and the paired paragnaths has a longitudinal groove, the oral groove, which is covered ventrally by the spinulose setae of the maxillae and laterally by the gnathobasal endites of the maxillules, these together forming an effective feeding apparatus. The midgut is produced anteriorly into a diverticulum which is higly secretory. In the middle portion of the midgut the epithelial cells are highly vacuolated. As they pass through this vacuolated region the gut contents are cemented into fecal pellets by a mucous secretion and they acquire a peritrophic membrane. There is a strong valve between the midgut and the hindgut. Peristalsis in the midgut is irregular but powerful and primarily in the reverse direction. The circulatory system involves a single heart, enclosed in a large pericardial space, and an anteriorly directed aorta terminating in an anterodorsal aortic sines. The latter communicates through three paires of openings with the sinuses in the head, which are in turn continuous with the perivisceral cavity, from which blood is returned to the pericardium. The heart has the form of a flask with an aortic valve at the tapered anterior end and a posterior ostium. The aortic wall is continued posteriorly over the heart and wraps around the anterior three-fifths as an outer membrane. This outer membrane is extended dorsally at three places to attach the heart to the dorsal exoskeleton; and it is also drawn out ventrally to form the anterior and lateral walls of the pericardium. These walls are continuous with the pericardial floor which seals the pericardia! cavity from the perivisceral cavity. The heart-beat and the blood flow through the system have been discussed. The excretory system consists of a pair of maxillary glands, each comprising a coelomic end-sac, a coelomic secretory tubule and an ectodermal excretory duct. The end-sac communicates with the tubule through a valvular opening. Antennary glands are not gound either in the nauplius stage or in the adult. The male reproductive system consists of a single testis and a single genital duct which is divided into four differentiated sections, the vas deferens, the seminal vesicle, the spermatophore sac, and the ductus ejaculatorius. The vas deferens is a thick-walled glandular tube secreting the various constituents of the spermatophore. The seminal vesicle serves mainly as a reservoir for the various components of a definitive spermatophore, and it is here that these take up their final positions. The spermatophore sac is highly glandular and is mainly responsible for formation of the coupling apparatus of the spermatophore. The spermatophore is not open directly to the outside but is connected with a canal system in the coupling apparatus. When transferred to the female genital segment at copulation, the central secretion of the spermatophore is discharged through the canal system of the coupling apparatus to glue down the spermatophore. A duct through which the spermatozoa can pass from the spermatophore to the spermathecae of the female appears to be formed later by an action of the female, possibly secretion of an enzyme or lysin. The discharge of the contents of the spermatophore is effected by swelling of Q-spermatozoa in the distal region of the spermatophore. The functional spermatozoa are spherical or polygonal and nonmotile. The female reproductive system consists of a single ovary, two oviducts, each with several diverticula, leading to the paired opnenings into the vaginal vacity, a pair of spermathecae and a pair of glands which open into the oviducts. In the mature female the oviducts are wide and sac-like, expanded by growing oocytes. However, the last portion of the oviduct is usually empty of eggs and is highly secretory. The oldest oocytes in the oviducts are usually at the metaphase of the first maturation division. The evidence points to the conclusion that the eggs are laid in this stage, and they are fertilized when they pass through the vaginal cavity. Oogenesis has been studied in detail. There are two periods of yolk formation: the first immediately after the dispersion of the mitochondrial bodies and the second in the last phase of the oocyte growth when the vacuoles in the cytoplasm are gradually replaced by yolk. Two dorsal ocelli, in the copepodid stages, are placed dorsolaterally against the exoskeleton and highly developed, each with a perfectly spherical, cuticular lens, while a single ventral ocellus remains unspecialized through the copepodid stages. Each dorsal ocellus proper is suspended in the head sinus by several connective tissue stands in addition to an aye muscle and consists of a large, syncytial pigmented cup occupied by a cellular sphere which is composed of 9 retinular and 4 crystalline cells. Each of the 9 retinular cells gives off an axon which leaves the ocellar cup at one of three places to proceed to the nauplius eye center in the protocerebrum. The ventral ocellus consists of two multinucleated pigmented cells, a cup-shaped tapetum, 6 retinular cells and about 8 conjunctival cells. Each of the 6 retinular cells sends an axon which loops over the posterior rim of the ocellar cup in common with the others to course to the nauplius eye center in the protocerebrum. The ventral ocellus is innervated by two afferent nerve fibers. There is also found a pair of conspicuous nerve fibers, possibly afferent, associated with the dorsal and ventral ocelli. A pair of accessory retinular groups, each consisting of three retinular cells, is found posterior to the dorsal ocelli. Three efferent aXOl1S from each group form a nerve running to the nauplius eye center in the protocerebrum. A pair of frontal organs, each innervated by a frontal nerve, lies in the anterior end of the head. The frontal nerves can be traced up to a pair of neuropiles immerdiately ventral to the nauplius eye center in the proto cerebrum. A pair of suprafrontal nerves branched off from the frontal nerves is found to innervate a pair of sensory filaments, the suprafrontal sensiIla, at the lower anterior end of the head. The central nervous system, consisting of a well developed brain connected by massive circumesophageaI connectives to the ventral nerve cord, has been described in detail. The ganglion cells are found throughout the nerve cord, and they are arranged into ganglia in the thoracic segments bearing the swimming legs. The stomatogastric nervous system has two pairs of labral and a single gastric ganglia. The medial pair of the labral ganglia forms anteriorly a single ganglion which is connected to the brain by three small nerves. The giant fiber system, consisting of giant motor fibers and giant interneurons, has been studied in detail, and it appears to constitute the effector portion of an escape reflex. The cutaneous glands opening through small pores in the cuticle of the metasome, urosome, and the appendages have been described. Chromatophores, unicellular or syncytial with several nuclei, are scattered deep in the body and are responsible for the metachrosis.