400 BOTANICAL GAZETTE [NOVEMBER 
Spermatogenesis in mosses.—The VAN LEEUWEN-REIJNVAANS add a few 
details to their former paper and announce their abandonment of this field of 
research,?9 after a brief excursion into it with rather startling results.3° Now 
they report centrosomes in the antheridial cells of Fegatella conica (contrary to 
BoLteteR) and in Pellia epiphylla (contrary to IkENo). In Mnium (sp. ?) they 
find (as in Polytrichum) in the last division from 8 to 4 chromosomes, 2 long and 
2 short, which is a transverse (not diagonal) reduction.—C. R. B. 
Acorus Calamus.—This species was introduced into Europe in the middle 
of the sixteenth century, and it has always been known that the European plant 
produces no seeds. A study of the development of the pollen and embryo cast 
by Micxes' shows that both are so defective that the production of seeds is 
impossible. The reason for the sterility is supposed to be unfavorable climatic 
conditions.—CHARLEsS J. CHAMBERLAIN. 
Germination of zoospores.—Continuing his studies upon the spores of algae, 
SAUVAGEAUS? describes the germination of the zoospores of Cladostephus, Algao- 
zonia, and Cutleria. Methods of making cultures of zoospores are also dis- 
cussed.—C artes J. CHAMBERLAIN. 
20 VAN LEEUWEN-REIJNVAAN, W. AND J., Ueber die Spermatogenese der Moose, 
speziell mit Beriicksichtigung der Zentrosomen- und Reduktionsteilungsfragen. Ber. 
utsch. Bot. Gesells. 26a: 301-309. pl. §. 1908. 
3° Cf. Bor. Gazette 45: 358. 1908; 46:234. 1908. 
3" Mtcke, M., Ueber den Bau und die cleat der Friichte und iiber die 
Herkunft von Dos Calamus L. Bot. Zeit. 66:1-23 
32 AGEAU, CAMILLE, Nouv_lles observations sur la germination du ox 
Stephus Bienes Sur la germination des zoospores de I’ Aglaozonia melanoides 
Sur la germination ole aerints du Cutleria adspersa. Sur les cultures cellulaires 
d’Algues. Compt. Rend. 63: 698-704. 1908. 
