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Multivariate statistical analyses are used to distinguish species in the genera Montastraea and Solenastrea through a continuous Neogene sequence (five Ma time interval) in the Cibao Valley of the northern Dominican Republic. Some older (by approximately 10 Ma) material from the same region also is included in the analyses. The material consists of approximately 280 colonies of Montastraea (74 of which are measured) from a total of 59 localities, and 66 colonies of Solenastrea (15 of which are measured) from a total of 37 localities. Twelve additional colonies of Montastraea from the Vokes' collections of the same localities are also measured, and added to the data set. The material is first sorted into the two genera on the basis of qualitative examination of septal structure, the structure of the columella and associated paliform lobes, and the texture of the coenosteum. Sixteen characters consisting of linear distances and counts are measured in transverse thin-sections of ten corallites per colony in Montastraea; ten similar characters are measured on the upper surface of ten calices per colony in Solenastrea. The data are analyzed using cluster and canonical discriminant analysis to group the colonies into clusters representing species. Seven species are so defined in Montastraea and two in Solenastrea. These groupings are then used statistically to reclassify type specimens for 12 of the 17 described species of Montastraea and four of the seven described species of Solenastrea. Three of the 12 species are synonymized in Montastraea, and two of the four species are synonymized in Solenastrea. Further qualitative study of the remaining types suggests that nine species of Montastraea and two species of Solenastrea existed altogether in the Caribbean during the Neogene. The stratigraphic range of two of the seven Dominican Republic species of Montastraea is shown to extend back to the Oligocene. Another of the Dominican Republic species is found to exist today, and is widely distributed throughout the Caribbean. Of the nine Neogene Caribbean species, only this species survived the Plio-Pleistocene extinction event. Only one species of Mantastmea is found to be endemic to the Dominican Republic. One of the remaining three species of Montastraea also has a limited stratigraphic distribution and appears confined to the southern Caribbean. Both species of Solenastrea appear to range from the Early Neogene to the Recent, and are widely distributed throughout the Caribbean. Trends within each species of Montastraea are analyzed through the sequence using nonparametric statistical procedures. Significant changes are detected upsection for at least four of the seven species in character complexes related to corallite size, septal development, and coenosteum development; however, significant correlations with species diversity suggest that these trends may be environmental in origin. Occurrence data suggest that two of the seven species of Montastraea may be indicative of shallow, nearshore conditions, whereas another two may be confined to muddy, and presumably deeper, patch reeflocalities. When data spanning the Oligocene to Recent are analyzed, significant directional trends are detected in one of the three longerranging Dominican Republic species; however, the amount of change does not exceed that observed within modern species. This suggests that, despite an apparent zigzag pattern, net stasis may be the rule in Montastraea. This study represents part of a multidisciplinary project on the paleontology and stratigraphy of the northern Dominican Republic, coordinated by P. Jung and J. B. Saunders of the Naturhistorisches Museum in Basel, Switzerland.
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.