236 BACTEEIOLOGY 



drop of potash solution, abundant mycelial threads are 

 seen, together with spores, -which are gathered in groups 

 resembling clusters of grapes. CultiYation on solid media 

 has not yet succeeded.] — Note by Translator. 



Certain observers, most recently M. Sabouraud, believe 

 that Trichophyton tonsurans really includes several distinct 

 varieties. The latter states as the result of an extended 

 research that there are two principal kinds, distinguished by 

 the size and arrangement of their spores and by their bio- 

 logical characters. The first, called by him Trichophyton, 

 microsporon, has spores 8/a in diameter which lie in no 

 particular order, and is apparently destitute of mycelium. 

 It occurs only in tinea tonsurans, causing about 60 per cent, 

 of the cases, and is most difficult to treat. On beer-wort 

 and agar it produces a growth which is at first white and 

 downy, but from the fifteenth to the eighteenth day becomes 

 dry, floury, and yellowish ; on potato it is dry and yellowish- 

 brown from the first. 



The other variety. Trichophyton macro- or megalosporon, 

 which causes all the remaining forms of tinea, is distinguished 

 by spores 7/i to S/x in diameter and arranged in lines in the 

 branches of its mycelium. Cultures show a white downy 

 growth, which appears a little later than in the case of the 

 former variety, and does not alter. On potato a reddish- 

 brown spot, like dried blood, appears ten days before the 

 white down develops. The macrosporon variety, however, 

 seems to include many species distinguished by further dif- 

 ferences in growth and producing distinct clinical phenomena. 

 One such causes about half the cases of tinea circinata, the 

 others are rare. 



The above-named varieties always reproduced the same 

 species, and the former could not be made to grow on any 

 part of the body except on the head. 



(See Ann. da Derm, et de Syph., vol. iii. Nov. 1892 ; also Brit. Journ. of 

 Derm., vol. v. Jan. 1893, and Med. Week, vol. i. Feb. 24, 1893.)— Te. 



