ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 87 



cetes is fully discussed. The author considers that there is a possibility 

 of relationship with the Floridete through the Laboulbeniaceae, though 

 convincing proofs of this are wanting, seeing that in no one of the Flori- 

 desG is there any approach to ascus-formation. The chlamydospores of 

 the different species are described ; they are frequently very abundant. 



Cytology of Capnodium and other Fumagines.* — M. G. Arnaud 

 finds that the septa of the cells of these fungi, as proljably those of all 

 the higher fungi, are traversed by a fine canal. The cells are uninucleate 

 except in Demathim puKulans, where not only the filaments but the 

 Toriila cells are plurinucleate. In Capnodium meridionale the concep- 

 tacles were developed without sexual fusion ; pycnidia and perithecia are 

 homologous in origin ; the ascogonium arises in a stroma that is almost 

 as large as the final perithecium. Filaments analogous with the pseudo- 

 trichogynes of CoIIema, Polystigma, etc. were noted, but they had no 

 connexion with reproduction. The mother-cell of the ascus is bi- 

 nucleate, but the very small size made exact observations very difficult. 

 Division is by mitosis, and the division spindle is extremely narrow. 

 There are four chromosomes as in other Ascomycetes. Mature spores 

 are uninucleate. 



Laboulbeniales. — Roland Thaxter f records a large number of new 

 genera and species of these minute fungi which were collected in 

 x\rgentina, chiefly in the Buenos Aires region, and mostly by himself. 

 The large series of forms obtained has enabled him to revise some of 

 the genera previously described, relationships and differences formerly 

 in doubt having been cleared up. Illustrations of the species are in 

 preparation. There have been added 9 new genera and G8 new species. 



Thaxter % has also published a second paper, with preliminary descrip- 

 tions of new species of Riclcia and Trenomyces. The species of Rickia 

 described were found on Acari. The genus is, he finds, a very variable 

 one. The characters of the antheridium differ to a large extent, and, 

 in some species, seem to be wholly lacking. The genus Trenomyces 

 occurs on Mallopliaga infesting domestic fowls, and was discovered 

 almost simultaneously in Italy, Germany, and France. It has since 

 been found in America. 



Polystigma rubrum.§— Y. Blackman and E. J. Welsford find from 

 their examination of this fungus that it possesses coiled multicellular 

 ascogonia which disorganize without producing ascogenous hyph^e. The 

 spermatia also are f unctionless, and show signs of nuclear disorganization 

 while still within the spermogonia. The ascogenous hyphte arise near 

 the ascogonia from vegetative hyphse. There is nuclear fusion in the 

 ascus, and some evidence for an earlier nuclear fusion in the ascogenous 

 hyphae at the time of their differentiation. Vegetative hyphse push 

 through the stomata, but there are no trichogynes. 



* Comptes Eendus, civ. (1912) pp. 726-8 (figs.), 

 t Proc. Amer. Acad. Arts and Sci., xlviii. No 7 (1912) pp. 155-223. 

 X Proc. Amer. Acad. Arts and Sci., xlviii. No. 10 (1912) pp. 365-86. 

 § Ann. Bot,, xsvi. (1912) pp. 761-7 (2 pis.). 



