222 SUiM-MAUY OK CURRENT KKSKAHCHES RELATING TO 



the Acrasieae has been already recorded. He now studies them in con- 

 nection with the development of true Mycetozoa, Didymium difforme 

 and Didymium diffusion. In nature the sporangia of these Myxomy- 

 cetes always contain numerous impurities, including a large series of 

 Bacteria. He proved by his cultures that the spores would not develop 

 without the accompanying bacterium, Bacillus luteus Fliigge. The 

 author draws attention to the formation of cysts in the sporangium ; 

 they are larger than the spores and without ornamentation on the 

 surface. These can persist for several years ; a sclerotium is but an 

 assemblage of cysts. He verified the observation that from the spores 

 of D. effusum and Spumaria alba zoospores are only formed in liquid 

 media ; on a solid substratum the spores give rise to myxamcebee. 



Further experiments were made with Plasmodiophora Brassicce,. Pinoy 

 describes his methods of preparing and obtaining pure cultures. He finds 

 that bacteria always accompany the spores. Their role in the host-plant 

 seems to be to destroy the tissue and secure the escape of the Plasmo- 

 diophora, but they exercise also some extracellular influence, as cultures 

 that contained no bacteria showed no signs of growth. It is evident 

 that the bacteria are introduced into the roots by the Plasmodiophora, 

 and then follows a true symbiosis between the two organisms. 



Stdegis, W. C. — The Myxomycetes of Colorado. 



[About 100 species have been published, with descriptive notes ; one new 

 species and two varieties are included.] 



Colorado Coll. Publ. Gen. Ser. 30, Sci. Ser. xii. (1907) No. 1, pp. 1-43. 



See also Ann. MycoL, v. (1907) p. 445. 



Schizophyta. 

 Schizomycetes. 



Sporulation of the Bacillus Rheumaticus.*— G. Rosenthal, from 

 observations on two varieties of the bacillus of Achalme, viz. B. per- 

 fringens and B. rheumaticus, finds that when subcultures of these two 

 organisms in albumen water are plunged into boiling water for two 

 minutes they all give a positive growth on incubation, but if exposed 

 for four minutes the cultures of B. rheumaticus are apparently killed, 

 whereas those of B. perfringens give a late but abundant growth with 

 irregular forms ; the same results were obtained when the cultures were 

 boiled for half a minute, showing that the two varieties have unequal 

 resistance to heat. Cover-slip preparations showed, in the case of the 

 perfringens cultures, typical sporulation ; but with B. rheumaticus, besides 

 some bacilli, there were a number of bodies about the size of Staphylo- 

 coccus aureus, that stained by Gram's method, resisted badly the decolora- 

 tion by acids when stained by Ziehl's method, and when unstained were 

 slightly refringent. 



Bacteriology of Tropical Abscess of the Liver.f — A. Gilbert and 

 A. Lipmann have examined pus from two cases of tropical abscess of 

 the liver. In the first case the pus was slightly odorous and of a brown 

 colour, and cover-slip preparations showed a number of cocci and rods 



* C.R. Soc. Biol. Paris, lxiii. (1907) p. 577. f Tom. cit., p. 565. 



