MICROSPORON MENTAGROPHYTES. - 155 



V. Species Microsporon mentagrophytes. Tab. Ill, figs. 1, 2, 3 

 = Oyptogames de la mentagre, Mentagrophyte = Cham- 



pignons de la mentagre 



The spores, which are in countless numbers, hang with one 

 part on the inner surface of the sheath of the hair, and the other 

 on the hair itself; they are round and very small. The filaments 

 or stalks are granulated inside, and divide themselves at an 

 angle of 40 to 80, in the shape of a fork. The branches are 

 annulated. 



Habitat. In the follicle of the hair of the beard, more especially 

 of the chin, the upper-lip, and cheek, and, according to Bazin, 

 also in the tufts of hair of the skin in general. 



This fungus is distinguished from the Microsporon Audouini by 

 larger filaments, branches, and spores, and by its seat. It also 

 penetrates into the follicle of the hair to its very root, between 

 the latter and the wall of the follicles. It settles neither in the 

 substance of the hair which lies in the follicle, like Trichophyton 

 tonsurans, nor around the part which is exposed to the air close 

 to the skin, like Microsporon Audouini. Thus M. mentagrophytes 

 forms, according to Gruby, a kind of vegetable sheath surrounding 

 and protecting that part of the hair which is imbedded in the 

 skin, and whose spores are never produced above the surface of 

 the skin. All the diseased parts of the hair are covered with 

 white, gray, and yellowish scales, from 2 6 mm. in breadth and 

 3 8 mm. in length ; they are a little convex in the middle, 

 forming angles a little depressed at the edge, and penetrated in 

 all places with hair. They are attached only slightly to the skin 

 underneath but firmly to the hair, and composed merely of 

 epidermis. The parasite begins to grow between the epithelium 

 of the follicle of the hair and rises along the hair till the latter 

 becomes exposed to the air. The epithelial cells themselves 

 change neither their transparency nor their shape, but only their 

 connection with one another which becomes loosened. The 

 parasite is found either primarily or secondarily on the simple 

 mentagra eczema or impetigo of the lips and nostrils. There 

 exists always, according to Bazin, at first a primary change in the 

 physical quality of the hair which is too often overlooked. The 

 eruption at first is either scattered or confluent ; some isolated 



