ZOOLOGY AND BOTANY, MICROSCOPY, ETO. 
131 
swelling of the coloured portion is observed. The anterior and posterio- 
ends are unchanged, as well as the cilia, but the two ends remain con- 
nected by a fine thread. If the same solution is applied to the spermator 
genous cells, the nuclei swell up, and finally are dissolved. 
If the spermatozooids are immersed for 24 hours in 0 • 5 per cent, 
hydrochloric acid, the central portion contracts, though it is still stained 
by iodine-green ; the number of coils is reduced from 2 J to scarcely 
one. The anterior portion and the cilia undergo no essential change ; 
numerous refringent granules or drops appear in the swollen posterior 
portion. This solution produces but little change in the spermatogenous 
cells. 
In a mixture of 1 part pepsin-glycerin and 3 parts 0*2 per cent, 
hydrochloric acid, after 24 hours the anterior end and the cilia of 
spermatozoids are still retained within the mother-cell disappear ; the 
central portion and the coils become narrower and closer. If free sper- 
matozoids are placed for some minutes in gastric juice, the anterior end 
becomes finely granular, the cilia disappear, the central portion becomes 
shorter and strongly refringent, the posterior end swells and becomes 
coarsely granular. 
In a fluid containing trypsin prepared after Kuhne’s method, the 
spermatozoids are finally completely absorbed, the process beginning 
with the central portion. 
These chemical reactions point to the same conclusion as the staining 
reactions, viz. the correctness of Belajeffs view,* that the central portion 
only of the spermatozoid is derived from the nucleus of the mother-cell, 
the anterior and posterior ends and the cilia from the cytoplasm. 
Determination, of Coniine and Curcumine.| — Herr A. Eossol gives 
the microchemical reactions, and the mode of demonstrating the presence 
of these two substances, the former in the tissues of the hemlock, the 
latter in the rhizome of Curcuma longa. Coniine he finds especially in 
the meristem of the growing point, and in the parenchyme of the sieve- 
portion of the vascular bundles. The action of potassium biniodide 
causes a red-brown precipitate soluble in sodium hyposulphite. Curcu- 
mine occurs in the parenchyme of the rhizome dissolved in an etherial 
oil. It is nearly insoluble in cold water and in glycerin, soluble with 
difficulty in hot water, in benzol, and in carbon bisulphide, readily 
soluble in alcohol and in ether, the latter solution showing a green 
fluorescence. Alkalies dissolve it with a red-brown, acids with a car- 
mine-red colour; this reaction with concentrated or moderately dilute 
sulphuric acid is the most useful. 
Sounding for Diatoms.^ — In the most recent of his series of papers 
on the technique of diatoms, M. J. Tempere describes the best modes 
of sounding ( sondages ) for diatoms, and of extracting them from the 
material thus obtained. When mud or sand has been obtained by 
dredging, the best mode of determining the presence of diatoms is the 
system of floating (Jlottage). The material is repeatedly agitated in 
water in a basin, and the scum which forms on the surface ladled off by 
* Cf. this Journal, 1893, p. 662. 
f JB. Nieder-ost. Land-Oberrealsch. Wiener-Neustadt, 1894. See Bot. Centralbl., 
lx. (1894) p. 174. I Le Diatomiste, ii. (1894) pp. 122-5. 
