Societies and Academies

Abstract

Society of Physics and Natural History, July 6. E. FBIEDHEIM, B. Susz and J. BAEB: The energy of activation and the temperature coefficient of a biological reaction. The respiration of the larvae of Diphyllobothrium latum. The considerable range of temperature over which these larvae live has led the authors to make a kinetic study with this parasite. The trend of the oxygen absorption curves is identical with that obtained in the case of a heterogeneous catalysis. E. JOUKOWSKY: On the frequent presence of pyrites crystals in the diatoms of a lake chalk: their probable bacterial origin. The author has found in a lake chalk diatoms containing pyrites in several forms. The iron arises from material dissolved or in suspension in the water. This hypothesis is one which it is possible to control by experiment. G. TIEBCY: Two theorems on ionisation in the Cepheids. The two theorems are based on the formula of the degree of ionisation. They show that the phase of maximum ionisation (the youngest spectrum) occurs after that of the maximum temperature and before that of the light maximum. M. GYSIN: Petro-graphical researches in the Haut-Katanga. (5). The formations of the system of Muva. This system includes the whole of the formations previous to the base conglomerate of Roan. The author distinguishes twelve principal types of rocks. G. GUTZEIT, M. GYSIN and R. GALOPIN: An attempt at the indirect chemical determination of the minerals in a polished surface by the drop test. A. WEINSTEIN: The theory of liquid jets taking capillarity into account. F. CHODAT and M. JUNQTJEBA: The endocellular hydrogen donators of yeast and their variation as a function of the age of the cultures. The authors give a report of their researches on the variation of the endocellular hydrogen donators of yeast with increasing age of the cultures. They add certain observations on the specific role of various buffer systems. L. REVEBDIN: The presence of a wedge in an un-described specimen from the older lacustral Neolithic. The author exhibits a specimen arising from the lower level of the neolithic remains of Port-Conty (Neuchatel). It is composed of a fragment of hollow stag's horn, fitted with a wooden handle. Microscopic examination shows that this handle has been perforated by a wedge of a different kind of wood. The complete instrument might be either a club or the end of a hatchet handle, the fragment of horn acting as a sort of grip. G. GUTZEIT, R. MONNIEB and R. BACHOULKOWA-BBUN: A new azo reagent for the magnesium cation, -acetylaminophenyl-5-azooxy-quinoline.