Die Revision

N. Fr. Pr.

Revision of the Cumacean Family Leuconidae

The family Leuconidae currently contains 99 species. With the exception of Epileucon, all genera in the family were established by 1907. All new species have been subsequently assigned to those genera, gradually producing genera distinguishable on the basis of single characters. In this paper Epileucon is reduced to a subgenus of Leucon as proposed by Bacescu (1988), and the species of Leucon are further apportioned among the subgenera Leucon Kroyer, Macrauloleucon, new subgenus, Crymoleucon, new subgenus, and Alytoleucon, new subgenus. In addition, the new genera Ommatoleucon, Austroleucon, Nippoleucon, and Bytholeucon are proposed, and the genus Coricuma Watling and Breedy is added to this family. The new genus Americuma, with unclear family affiliations, is proposed for a species previously assigned to Heteroleucon. Complete diagnoses are provided for all genera and keys are given to all genera and species.

Alfred Nossig's "Revision des Socialismus" [Rezension]

D. Farbstein

Richard Lichtheim: Revision der zionistischen Politik [Rezension]

E. G. F.

Na 50 Nachlass Arthur Schopenhauer - 'Schopenhauer-Archiv', 522 - Konzeptschreiben eines Rechtsgesuchs an den Justizminister Alexander von Danckelmann wegen der erfolgreichen Revision von Caroline Marquet in Sachen Körperverletzung

u.a.: Alimentation; Carolin Marquet; C.C.F. Kunowski;

Revision der im Exsiccat "Kryptogamen Badens von Jack, Leiner und Stitzenberger" enthaltenen Chytridiaceen, Peronosporeen, Ustilagineen und Uredineen

Von G. Lagerheim

Revision der Salix multiformis Döll mit besonderer Berücksichtigung der badischen Arten

Von Dr. J. A. Schatz

Revision of the early-middle Pleistocene calcareous nannofossil biochronology

The extant nannofossil biostratigraphic and biochronologic framework for the early-middle Pleistocene time interval has been tested through the micropaleontological analysis of globally distributed high-quality low- to mid-latitude deep-sea successions. The quantitative temporal distribution patterns of relative abundances of selected taxa were reconstructed in critical intervals, and the following biohorizons were defined: first occurrence of medium-sized Gephyrocapsa spp. (bmG); last occurrence of Calcidiscus macintyrei (tCm); first occurrence of large Gephyrocapsa spp. (blG); last occurrence of large Gephyrocapsa spp. (tlG); first occurrence of Reticulofenestra asanoi (bRa); re-entrance of medium-sized Gephyrocapsa spp. (reemG) and last occurrence of Reticulofenestra asanoi (tRa). The detailed patterns of abundance change at these biohorizons were used to generate a detailed biostratigraphy, and the biostratigraphic data were transformed into a precise biochronology by means of correlation to isotope stratigraphies and astronomical timescales. The degree of isochrony or diachrony of the biohorizons was evaluated. Biohorizons tlG and tRa are isochronous occurring close to marine isotope stages (MIS)55 and MIS 22, respectively, and bmG and blG are slightly diachronous on the order of 30-40 kyr, whereas biohorizons tCm, reemG and bRa are confirmed as diachronous on the order of 100, 80 and 60 kyr, respectively. Some of the events are clearly controlled by environmental conditions, e.g. the last occurrence of R. asanoi, related to significant environmental changes associated with the first large-amplitude glaciation of the late Quaternary, MIS 22.

Taxonomic lists and abundances of the Lower Miocene bivalve assemblages of the Vives quarry (Meilhan, SW France)

Biodiversity estimates through geological times are difficult because of taphonomic perturbations that affect sedimentary records. Pristine shell assemblages, however, allow for calibration of past diversity. Diversity structures of two exceptionally preserved Miocene bivalve assemblages are quantitatively determined, compared with recent communities and used as paleoenvironmental proxy. The extremely rich assemblages were collected in Aquitanian (Early Miocene) carbonate sands of the Vives Quarry (Meilhan, SW France). Both paleontological and sedimentological data indicate a coral patch-reef environment, which deposits were affected by transport processes. Among two samples more than 28.000 shells were counted and 135 species identified. Sample Vives 1 is interpreted as a proximal debris flow and Sample Vives 2 as a sandy shoreface/foreshore environment influenced by storms. The two Vives assemblages have a similar diversity structure despite facies differences. Rarefaction curves level off at ~600 shells. The rare species account for more than 80 % of the species pool. The high values of PIE diversity index suggest a relatively high species richness and an even distribution of abundance of the most common species within the assemblages. The fossil data are compared to death shell assemblages (family level) of a modern reefal setting (Touho area, New Caledonia). The shape of the rarefaction curves and PIE indices of Meilhan fossil assemblages compare well to modern data, especially those of deep (>10 m water depth), sandy depositional environments found downward the reef slope (slope and pass settings). In addition to primary ecological signals, the similarity of the Vives samples and the Recent deep samples derives from taphonomic processes. This assumption is supported by sedimentological and paleontological observations. Sediment transports gather allochthonous and in situ materials leading to mixing of various ecological niches. Such taphonomic processes are recorded in the diversity metrics. Environmental mixing and time-averaging of the shell assemblages disturb the preservation of local-scale diversity properties but favour the sampling of the regional-scale diversity.