280 



Mycologia 



Sexuality in the Basidiomycetes : — A Review of 



Bensaude, Mathii.de. Recherclies Siir Le Cycle Evolutif Et La Sexualite 

 Chez Les Basidiomycetes. Pp. 1-156, pi. 1-13, figs. 1-30. Nemours, 

 1918. 



The author of this extensive and what appears to be an ex- 

 haustive study of the nuclear phenomena in the myceha of 

 several Basidiomycetes brings again into the foreground the 

 fundamental problem in the mushrooms, namely their sexual 

 reproduction. 



Miss Bensuade confirms in a measure the observations of 

 Kniep (1915, '16, '17) who found that the clamp connections at 

 the cross walls of hyphal cells serve the purpose of keeping the 

 two nuclear elements of the die ar yon" apart and thus insure 

 the maintenance of two distinct lines of descent for the nuclei 

 which fuse in the basidium. Kniep claimed that the origin of 

 the binucleated condition is by the division of the nucleus of a 

 uninucleated cell. Miss Bensaude argues for the sexual signifi- 

 cance of the familiar hyphal anastomoses. Through the agency 

 of anastomosing cells (plasmogamy or pseudogamy) the binu- 

 cleated condition arises and this is perpetuated by conjugate 

 division in connection with clamp formation till the nuclei fuse 

 in the basidium. 



The mycelia of three autobasidiomycetes, Coprinus fimetarius 

 Fries, Armillaria mucida Schrad., and Tricholoma nudum Bull., 

 were studied in considerable detail. The author found Bouin's 

 picroformol the most satisfactory fixing agent and iron haema- 

 toxylin counterstained with cosine, light-green, or fuchsin, the 

 most desirable staining method. The work proper may be di- 

 vided into two parts : one dealing with the morphology and cytol- 

 ogy of the mycelia in general and the other with the study of 

 single spore cultures. 



The studies of mycelia were made on spore cultures and 

 mycelia gathered from the field. The author accepts R. Falck's 

 classification of the mycelia into primary, secondary, and tertiary 

 forms, and claims that during the first few days after germina- 

 tion the mycelium produced is primary in that the hyphae are 

 more or less partitioned ofif into cells which have from one to 



