56 MICROBES, FERMENTS, AND MOULDS. 
herpes; and that parasitic herpes may also be pro- 
duced on the back of the hand by the transference 
of the fungus from a patch of Timea tonsurans. 
The fungus may be transmitted to cats, dogs, and 
horses, who thus become agents of the contagion. A 
fresh study of the disease has been recently made by 
an Englishman, Dr. Thin, and he also regards it as 
identical with herpes, or Tinea circinata. 
According to this observer, the contagion is not 
transmitted by floating spores, but only by direct 
contact, and especially by the exchange of hats and 
caps so common among school.children. 
Experiments in artificial culture in milk, carrot- 
juice, or aqueous humour show that the fungus cannot 
be developed when the hair on which the spores are 
ig entirely submerged; a certain degree of moisture is, 
however, necessary, which is probably more frequently 
found on children’s heads. In adults, the bulbous root 
of the hair is dryer between the follicle and the skin. 
The parasite may be destroyed by causing an inflam- 
mation of the part affected, since the serous effusion 
thus produced places the hair in the same conditions 
as in the culture-liquids in which it is completely 
covered, and not floating. 
Pityriasis versicolor is produced by a fungus 
resembling the foregoing, termed Microsporon furfur. 
It grows between the cells of the epidermis, and 
effects their rapid degeneration. The hyphe have 
long articulations, intermixed with round spores, not 
