The Upper Triassic fishes from Polzberg bei Lunz, Austria

Carnian (Upper Triassic) fishes from Polzberg bei Lunz have been known since 1886 but no comprehensive account has been published. Eleven species are described nine of which, Saurichthys calcaratus, Polzbergia brochatus, Peltopleurus dirumptus, Habroichthys gregarius, Nannolepis elegans, Phaidrosoma lunzensis, Elpistoichthys pectinatus, E. striolatus and Pholidophoretes salvus are new, and two others, Thoracopterus niederristi Bronn and Gigantopterus telleri Abel, previously little-known.
New supraspecific taxa defined are:the order Polzbergiiformes, the family Thoracopteridae and the genera Polzbergia, Nannolepis, Phaidrosoma, Elpistoichthys and Pholidophoretes.
Habroichthys, Thoracopterus, Gigantopterus and Nannolepis show an unusual skull-roof pattern and are included in the re-defined order Luganoiiformes.
Two new ichthyokentemids considerably extend the known time-range of this family.
The genus Pholidophoretes is intermediate between the Archaeomenidae Goodrich 1909, and the Pholidophoridae sensu stricto Nybelin 1966.
The Polzberg assemblage was probably mainly marine with a small freshwater contribution; it shows less similarity to the Besano and Raibl assemblages than these do to each other.
The Luganoiiformes are probably, but not certainly, monophyletic; relationships within the order are analyzed and a cladogram constructed.
The Platysiagiformes, Peltopleuriformes, Luganoiiformes and Cephaloxeniformes could all have been derived from a common ancestor at the Perleidus level and are probably offshoots of the perleidid radiation.     

Winter Temperature as a Constraint to the Migration of Preindustrial Peoples

The dispersion of preindustrial peoples is strongly related to winter temperature in two surprising respects. Based on a classification of societies by language, we introduce a statistical model for their dispersion and show that (1) the 10°C (50°F) winter temperature isotherm has been an effective constraint to migration and expansion, and (2) the dispersion of language phyla has been remarkably homogeneous in a certain temperature scale, in contrast to the marked heterogeneity in terms of geographical dispersion , [climate, language, migration]     

Dimorphism in a Tethyan early Jurassic Juraphyllites

A lappeted microconch specimen of the phylloceratid ammonoid Juraphyllites from the Tethyan Jurassic of Anatolia (Turkey) indicates that sexual dimorphism in this group was established as early as in the early Lower Pliensbachian (Lower Jurassic) and that dimorphism in this genus of the Phylloceratina follows the same pattern as that proven [or many groups of the Ammonitina. This is the earliest record of well-developed lateral lappets in the Mesozoic Ammonoidea     

Uptake of DOM by Nemertean Worms: Association of Worms with Arthrodial Membranes

SYNOPSIS. Carcinonemertes errans is a nemertean worm, the juvenilesof which are found as epibionts on the Dungeness crab, Cancermagister, in close association with the arthrodial membranesof the crabs. The juvenile nemerteans appear to have no meansof taking in particulate food but survive for many months onthe surface of the host. We show that the juvenile C. erransare capable of removing amino acids from dilute solution insea water, that the water near the arthrodial membranes wherethe worms are found contains high concentrations of primaryamines, and that there is a low resistance pathway for low molecularweight amino acids across the arthrodial membrane examined invitro.     

Molecular and Subunit Heterogeneity of Legumin of Pisum sativum L. (Garden Pea)-- A Multi-Dimensional Gel Electrophoretic Study

Pisum sativum legumin has been shown to be heterogeneous withrespect to the existence of different molecular forms, the molecularweights of subunit pairs, and the molecular weights and isoelectricpoints of constituent subunits. Disulphide-bonded subunit pairswith mol. wt. 54 000 constitute a major part of total legumin.In addition, subunit pairs varying in mol. wt. from 35 000 to58 000 have been observed which associate in various ways togive rise to at least three distinct molecular forms of leguminseparable on non-dissociating gels. ‘Three-dimensional’gel electro-phoresis has been employed to understand the consitutionof these forms in detail.     

Nitrate Reductase Activity in Calcifugous and Calcicolous Tomatoes as Affected by Iron Stress

Calcicolous plants are generally more Fe-efficient than calcifugous plants, because they respond to Fe stress by releasing H-ions and “reductants” from their roots that causes Fe to become available. The objective of our study was to determine if differential response to Fe stress in calcicolous and calcifugous varieties affects nitrate reductase activity. T3238FER (Fe-efficient) and T3238fer (Fe-inefficient) tomato (Lycopersicon esculentum Mill.) cultivars were grown in nutrient solutions supplied with N as NH₄⁺-N plus NO₃^?-N, and as NO₃^?-N only. The chemical reactions induced by Fe stress concomitantly increased nitrate reductase activity in roots and tops of calcicolous, but not in calcifugous tomato. This nitrate reductase activity decreased, however, when Fe was made available to the plants. When Fe stress was eliminated by adding Fe, nitrate reductase activity was comparable in the two cultivars.     

Experimental studies on nymphal growth in Leptophlebia vespertina (L.) (Ephemeroptera)

The mayfly, Leptophlebia vespertina (L.) was reared at field temperatures in the laboratory. The egg incubation period was 21–26 days. There were seventeen to nineteen nymphal instars. Growth was generally rapid during the first 3½ months and slow thereafter. This change occurred at the same time in both the laboratory and the field population. Temperature is considered to be the major factor regulating this and other changes in growth rate.     

MDMP Action: Degradative Effects on Polyribosomes from Wheat Roots and the Inhibition of Protein Initiation

The rapid action of MDMP in promoting the conversion of polyribosomesinto monoribosomes in wheat roots suggests that the compoundmay interfere with the attachment of ribosomes to messengerRNA. The action is stereospeeffic: the L-lsomer has no effecton polyribosomes and does not compete with D-MDMP with respectto polyribosome degradation or the inhibition of initiation-dependentamino acid incorporation in vitro.