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The total bases from Gonioma kamassihave been divided into tertiary and quaternary fractions and electrophoretic patterns of these are shown. The LD50 values for mice of the various fractions have been determined. The curariform action has been located in the quaternary fractions, and potencies estimated in comparison with tubocurarine. The curariform action has been shown to be truly neuromuscular, and strong evidence presented that the action is depolarising. Effects on respiration and duration of blocking action, compared with tubocurarine have been shown, and the presence of a prolonged parasympathetic ganglion blocking activity in the quaternary fraction is also demonstrated.

Three crystalline materials have been isolated from the leaves of Bersama abyssinicasub. sp. abyssinica, N.O. Melianthaceae. Some chemical and pharmacological evidence is presented that these materials are bufodienolide aglycones. The material isolated in greatest quantity has a toxicity similar to that of scillaridin.

Le Lac George, lac équatorial et peu profond, est entouré de végétation semi-aquatique. Les espèces libres surnageantes, surtout Pistia stratiotes, sont abondantes. Les espèces submergées sont absentes dans la plupart du lac. La végétation du littoral peut être divisée en trois groupes. D'une part on trouve ça et là des plages sableuses aux eaux agitées, avec des étendues de Paspalidium geminatum parallèles aux rives. D'autre part on peut distinguer deux groupements des rives vaseuses, avec ou sans Cyperus papyrus. Le broutement des grands mammifères est probablement un facteur modificateur assez fort de la végétation. L'absence des espèces submergées est discutée et attribuée a la transparence faible de l'eau, à cause des fortes populations des algues planctoniques. La végétation est comparée avec celle des autres grands lacs de l'Afrique Centrale.

The magnetization of alloys of neodymium with lanthanum has been measured from room temperature down to 1-5°K. Above about 15°K the susceptibility is field-independent and obeys a Curie-Weiss law modified by a small temperature-independent paramagnetic term, χ = C(T-θ) + K. The Curie constant C gives effective atomic moments for all alloys in approximate agreement with the theoretical value for the Nd3+ ion, 3-62 μBper atom. At lower temperatures the alloys show striking saturation effects, and it is suggested that this can be accounted for in terms of a model in which the magnetic interactions between neodymium atoms are anti-ferromagnetic for nearest neighbours but ferromagnetic for more distant neighbours.

Specific heat measurements between 1.5°k and 20°k, and magnetic susceptibility measurements between 1.5°k and 290°k have been made on four alloys containing respectively 78.9%, 37.6%, 27.0% and 5.03% by weight of cerium in lanthanum. Comparison is made with similar previous measurements on pure cerium. The single anomaly in the specific heat of pure cerium at 12.3°k. splits into two in the alloys, and as the dilution is increased these anomalies move to lower temperatures. The lower of the two only is accompanied by a change in the magnetic properties, a maximum occurring in the susceptibility of the most concentrated alloy and temperature-independent paramagnetism setting in suddenly in the next two. In the most dilute alloy the anomalies in both the specific heat and in the susceptibility appear to have moved to temperatures below 1.5°k. Above 80°K the magnetic susceptibilities of all the alloys obeyed a Curie-Weiss law, σ = C/(T-θ). The Curie constant C varied smoothly from 56-1 × 10-4 e.m.u./g Ce for the most concentrated alloy (cf. 55-3 × 10-4 e.m.u./g for pure cerium) to about 140 × 10-4e.m.u./gCe for the most dilute alloy.As in pure cerium, anti-ferromagnetism is believed to be the explanation of the anomalous magnetic behaviour of the alloys. However, the double specific heat anomalies in the latter suggest that the ordering of the 4f electronic orbitals takes place in two stages, while the temperature-independent paramagnetism of the more dilute alloys may be the consequence of freedom of the direction of magnetic ordering to orient itself perpendicular to the applied field. The increase in the Curie constant suggests that the population of the 4f shell increases, with dilution of the alloys, to 2 or 3 electrons per atom of cerium.