172 Transactions British Mycological Society. 



year, however, the flux is somewhat gritty owing to the presence 

 of crystals of calcium carbonate dissolved from the cell walls 

 of the wood and redeposited in the flux, and contains certain 

 characteristic fungi. In very old fluxes few fungi are found and 

 the brown porridge-hke masses are composed mainly of small 

 pieces of disintegrated wood. Insect larvae are abundant, and 

 very characteristic. Protozoa, nematodes, etc., are also common. 



The writer is much indebted to Dr D. Keilin, of the Molteno 

 Institute for Research in Parasitology, Cambridge, for the 

 following list of the insect larvae found in a brown flux at 

 Cambridge which are typical : — 



Dasyhelea obscura Winnertz (Ceratopogonidae) , Mycetobia 

 Pallipes Meig. and Rhyphus fenestralis Scop. (Rhyphidae), 

 Phaonia cincta Zett ( Anthomyiidae) , Aulacogaster rufitarsis Mcq. 

 (Ephydridae), Systenus adpropinquans Loew. (Dolichopopidae) , 

 and an Eristaline (Syrphidae). A mite, Hericia hericia (Robin) 

 Kramer (Acarina, Tyroglyphidae) , was very common. Some 

 very interesting parasites were found in certain of these larvae*. 



(b) Organisms present. 

 A. Oospora sp. (?) 



This is one of the most interesting of the organisms which 

 have been isolated from the slime-fluxes. It occurs constantly 

 in the brown fluxes of elms and horse-chestnuts. 



Cultural characters. On potato agar, Dox's agar, etc. small com- 

 pact colonies appear after four or five weeks. On beer-wort 

 agar rapid growth (appears after five days at 26° C); on this 

 medium and on sterile carrot somewhat hard sand-coloured 

 masses or nodules are formed which become white and flocculent 

 when old and dry. 



Morphological characters. As it appears in the flux, the fungus 

 consists of strings of oval to globular cells, about 5*5 ju, in 

 diameter, with large vacuoles. Cell multiplication is by budding. 

 The white flocculent growth on carrot and other media consists 

 of branching aerial hyphae arising from a creeping mycelium, 

 the cells of which, however, are little different from the ordinary 

 budding cells. 



The fungus appears to agree with the somewhat meagre 

 diagnoses given by Ludwig and others of Torula monilioides 

 Corda, except in the fact that on no culture media has the writer 

 observed any brown colour microscopically, such as was de- 

 scribed by Ludwig. A brown colour has occasionally been noticed 

 in certain of the cells in the crude flux, but this is probably due 

 to staining or to a moribund condition of the cells. 



* See Keilin, D., in recent numbers of Parasitology. 



