ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
75 
geotropic stimulus, tlie roots were made to revolve slowly round their 
own axis in a klinostat. It was found that if a root is so placed that the 
terminal part points vertically downwards while the rest is horizontal, no 
geotropic curvature takes place; but that such curvature is exhibited 
when the terminal portion is directed horizontally or at an acute angle 
with the normal position. 
Function of the Apex of the Root.* — Dr. W. Rothert 1 gives a de- 
tailed resume of the literature of the phenomena of sensitiveness con- 
nected with the root — geotropism, heliotropism, aerotropism, hydro- 
tropism, galvanotropism — and the effect on these phenomena of the 
decapitation of the apex. Thermotropism appears to belong to the whole 
growing region of the root ; but, with regard to the other properties, it 
cannot yet be determined whether they are confined to the apical region, 
or whether they belong to this region chiefly, and in a less degree to the 
rest of the growing portion, or are uniformly distributed over the whole 
of the growing portion. There is no evidence in support of Darwin’s 
hypothesis of a “ brain function ” of the apex of the root. 
(40 Chemical Chang-es (including Respiration and Fermentation). 
Germination of Oleaginous Seeds.j — M. Leclerc du Sablon states 
that in the germination of oleaginous seeds — hemp, flax, colza, poppy, 
Aracliis , Bicinus — a chemical change takes place similar to that in amy- 
laceous seeds, viz. a transformation of the oil into a saccharose with but 
little or no reducing power, and finally into glucose. 
Metastasis and Respiration of Germinating Potatoes. J — After 
experiments with germinating potatoes, seedlings of Lujpinus luteus , and 
other plants, Herr E. Ziegenbein asserts that the decomposition of albu- 
minoids in the growing plant is independent of the action of the free 
oxygen of the air, and also of the action of light, although light appears 
to produce conditions which favour the subsequent production of carbon 
dioxide. Various results are also given respecting the influence of 
different temperatures on metastasis and respiration. 
Respiration of Leaves.§ — M. L. Maquenne finds that the amount of 
carbon dioxide evolved by leaves in the process of respiration is greatly 
reduced by placing them in a vacuum ; from which he draws the con- 
clusion that the evolution of carbon dioxide in this process is not merely 
the doubling of an already oxidized substance, as in fermentation, but is 
a true oxidation. 
B. CRYPTOGAMIA. 
Cryptogamia Vascularia. 
trobilus in Archegoniatae.|| — Prof. F. 0. Bower proposes a theory 
of the origin of the strobilus in a simple form like that of Equisetum, and 
its gradual development in the higher divisions of Vascular Cryptogams 
* Flora, Ixxix. (1891) Erganzungsbd., pp. 179-218. 
t Comptes Eendus, cxix. (1894) pp. 010 2. Cf. this Journal, 1894, p. 230. 
* ‘ Unters. iib. d. Stoffwechsel u. d. Athmung keimender Kartoffel-Knollen, u.s.w. / 
Berlin, 1893, 48 pp. and 1 pi. See Bot. Centralbl., lx. (1894) p. 145. 
§ Comptes Eendus, cxix. (1894) pp. 100-2. 
|| Ann. Bot., viii. (1894) pp. 343-65. 
