380 Algae. 



found to be more difficult to raise carposporelings to maturity than 

 tetrasporelings, for the reason that tetrasporic plants are usually 

 late in fruiting, while sexual individuals may be expected to pro- 

 duce reproductive bodies in 3 to 5 weeks. The experiments show, 

 however, that in Gviffithsia and Dasya the tetraspores actually do 

 produce sexual plants, and only these, and that in Polysiphonia 

 violacea carpospores produce only tetrasporic plants. The results of 

 the experiments go to show, therefore, that the conclusions drawn 

 from cytological evidence are valid, and that alternation of sexual 

 and tetrasporic plants in the Florideae is now an observed fact. 

 Araong other conclusions it is noted that "there is no evidence that 

 the double number of chromosomes in the carpospores imparts 

 greater vigor of growth as compared with the Single number of 

 the tetraspores." Maxon. 



Mc Fadden, M. E„ O n a Colacodasya from s o u t h e r n Cali- 

 fornia. (Univ. California Publ. Bot. IV. 8. p. 143—150. pl. 19. 

 Febr. 25. 1911.) 



Following a brief review of the literature of parasitic species 

 of Florideae the writer describes, as new, Colacodasya verrucaeformis 

 Setchell and Mc Fadden, from material coUected on Mychodea 

 episcopalis J. Ag. at San Pedro, California. This new species 

 is figured in section. Maxon. 



Mc Fadden, A. S., The nature ofthe carpostomes in 

 the cystocarp of Ahnfeldtia gigartinoides. (Univ. California 

 Publ. Bot. IV. 7. p. 137-142. pl. 18. Febr. 25, 1911.) 



As the result of a comparative study the author maintains that 

 material from Lands End, near San Francisco, California, 

 which has usually been called Ahnfeldtia gigai'tinoides].G. Agüivdhy 

 is correctly named and that it represents a species amply distinct 

 from A. concinna of the Hawaiian Islands. A cystocarp of ^. 

 gigartinoides is figured in cross section, showing spores and car- 

 postomes. Maxon. 



Ostenfeld, C. H., A Revision ofthe Marine Species of 

 Chaetocerns E h b g. sect. Simplicia O s t f . (Medd. Kommiss. f. 

 Havundersögelser, Serie Plankton. I. 10. 11 pp. 24 figs. Köbenhavn. 

 1912.) 



The distinction between the species of the genus Chaetoceras 

 has been rather a difficult task; this applies especially to the small, 

 faintly siliceous species of the sect. Simplicia. The author has had 

 access to most of these species and often to the original samples 

 from where they were described and gives in the present paper a 

 revision of the hitherto described marine species. According to this 

 re Vision the number of marine species of the section is only six, 

 viz.: Ch. distinguendum Lemm. [Ch. clavigera Ostenf., non Grün.), 

 Ch. Simplex Ostf. {Ch. subsalsum Lemm., Ch. Borgei Lemm.), Ch. 

 gracile Schutt (non Pauls., nee Apstein; Ch. septentrionale Cleve, 

 non Oestr.), Ch. septentrionale Oestr. (Ch. gracile Pauls,, Ch. glaciale 

 Meunier), Ch. ceratosporum Ostf. (? Ch. tortilisetus Mangin). Ch. 

 Vistulae Apst. 



All the hitherto published drawings of these species and several 

 new drawings are given as figures in the text; each species is descri- 



