ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
225 
Antirrhinum, and Pelargonium. It is quite independent of the protoplasm, 
and can be extracted by treatment with dilute glycerin. This presence 
of diastase may be of great physiological importance in connection with 
the power of the pollen-tube to avail itself of the nutriment obtained 
from the tissue of the style, as germination proceeds through its later 
stages. 
Oil-decomposing Ferment in Plants * — Pursuing his investigations 
on this subject, Dr. W. Sigmund finds a considerably larger proportion of 
fatty acid in germinating seeds than in seeds in the dormant condition ; 
and this seems to be especially the case when they germinate at high 
temperatures. The observations were made on the seeds of the turnip, 
hemp, poppy, flax, &c. 
Chemical Composition of Leguminous Seeds.f — Herren E. Schultze, 
E. Steiger, and W. Maxwell give a detailed account of the composition of 
lupin seeds and of the methods employed in estimation of the various con- 
stituents. Analyses of the seeds of Vieia sativa,Pisum sativum, and Faba 
vulgaris are also given, and the seeds of Soja hispida are mentioned as 
being somewhat remarkable in that they contain more cane sugar than 
the others. They also contain 1 • 64 per cent, of lecithin. 
(3) Structure of Tissues. 
Laticiferous tubes of Euphorbiacese, Urticacese, Apocynace®, and 
Asclepiadece.f — M. L. G. Chauveaud has carefully examined the origin 
of the laticiferous tubes in these three natural orders. 
In the Euphorbiace® (the researches having been chiefly confined to 
the genus Euphorbia) the mode of the first development of the latici- 
ferous apparatus is not uniform, the difference depending mainly on the 
number of initial cells present in the embryo. As a general rule these 
initial cells are numerous, and form, in the first place, a complete layer 
surrounding a central cylinder, the exact structure of which is uniform 
in each species. In some species the number of these initials is reduced 
to eight, or even to four. The generating layer of these initials is 
always situated in the “ nodal plane,” which coincides with the base of 
insertion of the cotyledons. No anastomosings could be detected, either 
of the laticiferous tubes among one another, or between these tubes and 
the adjacent tissues. 
In the Asclepiade® and Apocynace® we find a somewhat different 
type; in some of these the embryo has no cortical prolongation in its 
tigellum. In the Asclepiade® the central tubes are generally inflected 
in the region of the collar ; they leave the central cylinder and penetrate 
the cortex, in the interior of which they continue their growth. 
In the Urticacere the initials of the laticiferous tubes are arranged in 
groups of five in the face of tho two notches in the cotyledons. 
In its development, during germination and subsequently, the latici- 
ferous apparatus preserves essentially tho same arrangement that it 
presents in the embryo as far as the stem and its branches are con- 
* SB. K. Akad. Wiss. Wien, c. (1891) pp. 328-35. Cf. this Journal, 1891, p. 221. 
t Landw. Versuchs-Stat., xxxix. pp. 269-326. See Journ. Cliem. Soc., 1891, 
Abstracts, p. 1541. 
f Ann. Sci. Nat. (Bot.), xiv. (1891) pp. 1-161 (8 pis. and 3 figs.). 
