502 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
Algae. 
Cystocarps and Antherids of Catenella Opuntia.* * * § — Mr. R. J. 
Harvey-Gibson describes the hitherto but little known cystocarps and 
antherids of this species of red sea- weed. The cystocarps are immersed 
in ramifications of the erect branches; they are spherical, and each 
ramification contains from 50 to 150 procarps, of which, however, but 
few arrive at maturity. Each procarp consists of a single carpogenous 
cell, a single trichophore-cell, and a very long delicate trichogyne. 
After impregnation each carpogenous cell gives birth to from 12 to 20 
carpospores. The antherids are also formed on special branches. 
Galls on a Sea-weed.f — Miss E. S. Barton describes pathological 
structures found in the frond of Bhodymenia palmata , which appear to 
be the result of a stimulus caused by the attacks of a marine Crustacean, 
Harpacticus clielifer. They have the appearance of minute papillae ; and 
in the cells of these papillae, as well as in diseased portions of the thallus 
in their neighbourhood, were found remains of the bodies of the attack- 
ing animal, and in some instances its eggs. 
Structure and Development of Chylocladieae.l — Pursuing his 
investigation of the structure of the genera Chylocladia, Champia, and 
Lomentaria , especially as regards their vegetative organs, M. F. Debray 
distinguishes, in all the species examined, between the primary and 
secondary axes. The former is often short and always solid ; and its 
peripheral portion consists of dichotomously divided rows of cells which 
become smaller towards the surface. The attachment- disc increases on 
the whole of its upper side by division of the terminal cells of erect 
rows. The secondary shoots grow from the primary axis either by 
lateral growth near the apex, or by actual prolongation of the apex. 
Special peculiarities of structure are described in Chylocladia rejlexa, 
C. ovalis , Lomentaria clavellosa, and L. articulata. 
Conjugation of the Zygnemacese.§ — Mr. W. West confirms the view 
taken by Bennett |] and others as to the sexuality of the filaments of 
the Zygnemace® ; all the cells in the same filament appear to be 
invariably of the same character, either active or passive, in the act of 
conjugation. He has frequently observed lateral conjugation in cells of 
a filament, some of the cells of which are in scalariform conjugation 
with those of another filament. As regards the conjugation of more 
than two filaments, he finds, like previous observers, polygamy to be 
much more common than polyandry. 
Clamp-organs of the Conjugatae.f — M. P. A. Dangeard describes 
root-like organs by means of which some species of Zygnemaceae, which 
usually float free in the water, can attach themselves to a solid substance. 
They were observed in Zygogonium pedinatum and in an undescribed 
species of Spirogyra. 
* Neptunia, i. (1891) pp. 5-6. 
t Journ. of Bot., xxix. (1891) pp. 65-8 (1 pi.). 
I Bull. Scient. France et Belg , xxii. (1890) pp. 399-416 (17 figs.). See Bot. 
Centralbl.. xlv. (1891) p. 21. Cf. this Journal, 1888, p. 265. 
§ Neptunia, i. (1891) pp. 81-5 (2 pis.). || Cf. this Journal, 1884, p. 434. 
^ Le Botaniste (Dangeard), ii. (1891) pp. 161-2, and 228 (1 pi.). 
