488 MEDICAL MYCOLOGY 



knob, covered with delicate white velvet; on 4% glucose, best growth, deep 

 red, color diffusing to media in old culture, the whitish velvet may hide the 

 red color.] On ordinary agar, white colonies with central knob and greenish 

 margin, no red pigment. 



This species has often been confused with E. purpureum (Bang) Dodge 

 which was published with a much more complete description within a few weeks. 

 This name has been used for several species with red colonies, generally caus- 

 ing lesions in the epidermis, and Kato has reported a fungus by this name 

 from tinea tonsurans of the endothrix type (perhaps a red member of the 

 Favofrichophyton violaceum group). Such reductions to synonymy as those of 

 Hashimoto, Irizawa, and Ota (1930) which show no evidence of a careful study 

 of cultures referable to the various descriptions, are only confusing. Their 

 white variety differs in cultural characters and in ability to infect guinea pigs 

 from both species to which they refer it as synonyms and seems to be a species 

 oi E dot rich ophy ton (see E. Otae, p. 500). 



Recently Muskatblit (1933) has made a comparative study of strains which 

 he has referred to E. purpureum and E. ruhruni. He describes E. ruhrum as 

 follows: Mycelium frequently tortuous, thick and irregular, with numerous 

 chlamydospores and large closterospores with blunt ends and thin smooth 

 walls ; aleurospores not reported. Colony has a central knob with a smooth, 

 irregular surface and waxy yellowish becoming cerebriform, powdery, the 

 convolutions tending to become deep radial furrows toward the margin which 

 is flat and even, center deep red becoming lighter toward the periphery, pig- 

 ment slightly diffusing into the medium ; finally develops pleomorphic my- 

 celium. On conservation agar, colony similar but yellowish with a lilac color 

 in the center. 



Epidermophyton Pemeti Castellani, Brit. Jour. Derm. Syphilis 22: 148, 

 1910 ; Castellani & Chalmers, Man. Trop. Med. ed. 1, 610, 1910. 



"Growth more rapid than in E. cruris. [E. floccosum.] Colonies on maltose 

 a delicate pink, rare, color disappearing in subcultures." 



The above description is too brief to be of any value in view of the number 

 of species of this genus which have pinkish colonies. It might be pointed out 

 that this specific name antedates all others in the group and that this name, not 

 ruhrum, must be used by those who would unite these species with pink and 

 red colonies. 



Doubtful Species 



The following species have been too poorly described to place definitely. 

 Perhaps they belong in Epidermophyton. 



Trichophyton ceylonense Castellani, Jour. Trop. Med. Hyg. 11: 261-268, 

 1 pi, 1908; Arch. Derm. Syphilis 93: 40, 41, 1908. 



Atrichophyton ceylonense Castellani & Chalmers, Man. Trop. Med. ed. 3, 

 1009, 1919. 



Reported as the cause of tinea nigromarginata, causing thick, reddish, ele- 

 vated rings, darker in the center, with pruritus on scrotum and neck, Ceylon. 



