ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
663 
previous observers differ. The material was fixed with osmic acid and 
alcohol, or with Flemming’s mixture, and double-stained with fuchsin 
and iodine-green. 
The author distinguishes three portions of the antlierozoid — a slender 
anterior, a central, and a thicker posterior portion, the first and last 
each including about half a coil, or rather more. The anterior part is 
stained red by the mixture ; the cilia which it bears are also stained red ; 
these are not placed, as is usually stated, at the apex of the antherozoid, 
but near the base of the anterior portion. The central portion is stained 
blue-green, but has an extremely delicate rose-coloured envelope. The 
posterior portion is stained red, but less intensely than the anterior part. 
From these reactions the author concludes that only the central portion 
of the antherozoid is formed from the nucleus of the mother-cell. 
The mode of development and the structure of the mother-cells of 
the antherozoids are described in detail, and direct observation supports 
the conclusion derived from the staining reactions, that the protoplasm, 
independently of the nucleus, plays an important part in the formation 
of the antherozoid. The cilia are from the first entirely free from the 
body of the antherozoid. 
Algae. 
Reinke’s Atlas of German Seaweeds. — Three more parts (iii.-v.) 
of the second volume of this valuable work are now published, and 
include 15 plates. The genera treated of are — Stilophora , HalorJiiza , 
Chordaria , Bhodocorton, Ectocarpus, Pogotrichum , Sphacelciria , and 
Stypocaulon. 
Plurilocular Sporanges of Chorda filum.*— Mr. T. H. Buffham 
describes the plurilocular sporanges in this genus of seaweeds. The 
axis of the plants on which they occur was always found to be twisted 
spirally. 
Variability of Desmidiese.f — From the examination of a large number 
of individuals of a species of Cosmarium Herr W. Schmidle comes to the 
following conclusions with regard to the limits of specific variability, 
which are probably true of all desmids, viz. : — The structure of the 
chlorophyll is constant in the same species ; the form of the cell varies 
within narrow limits ; the apical appearance is constant; the granulation 
is very variable. 
Apiocystis.J — Under special conditions of growth, Herr C. Correns 
finds, in Apiocystis Brauniana , besides megazoospores, microzoospores 
formed by repeated division of the vegetative cells ; no conjugation 
between them was observed. He describes also the occurrence, on the 
fixed colonies, of “ pseudo-cilia,” motionless cilium-like bodies, proceed- 
ing in pairs from each cell. These have no connection with the true 
cilia of the zoospores, and take no part in their formation; they are 
more akin to the hair-like structures of other algse. They are formed 
after the zoospore has come to rest, and each consists of a gelatinous 
sheath and a central thread of protoplasmic nature. When a cell divides, 
* Grevillea, xxi. (1893) pp. 86-8 (4 figs.). 
t Hedwigia, xxxii. (1893) pp. 109-15 (11 figs.). 
% Beitr. z. Morph, u. Phys. d. Pflanzenzelle (Zimmermann), Heft iii. pp. 241-59 
(2 figs.). See Bot. Centralbl., liv. (1893) p. 146. 
