ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 325 
genus and of allied forms which may be summarised by the following 
table : — 
Frondicularia Nodosaria 
(including Flabellina ) 
Sagrina 
Cristellaria Uvigerina 
Primordial Form 
Adherence of Amoeba to solid bodies.* — M. F. Le Dantec has 
made experiments which enable him to confirm the statement of 
Bruno Hofer that Amoeba proteus moves along the surface of solid bodies 
placed in water, and that this mode of crawling is indispensable if the 
animal is to feed itself. The author points out that he has shown else- 
where that the protoplasm of the Amoeba has an outer layer which in 
contact with water is of high superficial tension. When an Amoeba is 
completely extended, its lower face has become a plane parallel and very 
close to the plate that holds it. Adhesion is effected by molecular 
attraction. The adhesion is never very energetic. 
Thermotaxis of Euglena.f — Dr. E. de Wildeman has made a number 
of experiments showing how Euglena viridis behaves in relation to heat. 
In the first place, he mixed the Protozoa in a tube with sand, in order 
to avoid convection currents, placed the tube horizontally in darkness 
near a source of heat, and found that all the Euglense accumulated 
towards the upper part and the warmer end. The same result was got 
when the Protozoa were kept in fluid. When capillary tubes were used, 
in darkness , the animalcules sought the warmer parts, which were how- 
ever those with most oxygen. If the crowded end was cooled they 
shifted to the other. But when the tubes were placed at right angles 
to rays of the light, the organisms avoided the heat ; if the tubes were 
placed in the same direction as the rays of light they sought the end 
* Comptes Rendus, cxx. (1895) pp. 210-3. 
t Bull. Soc. Beige Micr., ix. (1894) pp. 245-58. 
