42 



The Natuealist. 



of the epidemic, and tlie sous-prefet summoned tlie Con sell 

 d' Hygiene to take action, and in consequence it is announced that 

 this curious epidemic has now entirely disappeared. 



The term is loosely used, but the real ringworm is caused by a 

 cryptogamic fungTis which was first described by Malmsten in 1845. 

 An extensive literature of herpetic eruptions is chronicled by 

 Dr. James Copland, in his Dictionary of Practical Medicine (London, 

 1858). The result of more modern inquiries is given in Aitken's 

 Science and Practice of Medicine (London, 1872), from which the 

 following description of the parasite is taken : " It consists of oval 

 transparent spores or globules y^orr P^^'* ^^^^ diameter. 



Many of these are isolated ; others constitute, by their juxtaposition, 

 articulated filaments. Comparatively few cryptoganiic tubes are 

 visible — a character which distinguishes the ringworm affections from 

 the vegetable structures seen in other diseases of the skin. Its 

 anatomical seat is in the interior of the roots of the hair. The hairs 

 and fungi simultaneously increase ; the former seem larger than 

 usual, are paler in colour, lose their elasticity, soften and break off 

 when they have risen some one or two lines above the surface of the 

 scalp. In the short cylinder of hair left, the fungus grows still more 

 rapidly, so that the normal structure of the small stump soon becomes 

 undistinguishable. Sometimes the hair breaks off before emerging 

 from the skin, and the fungus, epidermis and sebaceous matter fill the 

 ends of the piliferous conduits and form the little prominences which 

 can be seen by the naked eye in this disease, and which gives to the 

 skin a rough anserine appearance. The sporules and mycelium of 

 the plants can sometimes be seen in the form of a white powder on the 

 roots of the broken hairs ; sometimes the cutis becomes congested and 

 thickened, and then the plant becomes mixed up with the scales of 

 the epidermis, with fatty and albuminoid granules, with pus and 

 serous exudation, and so crusts are formed of greater or less thickness 

 in which the growth of the fungus can go on. It exists in the Herpes 

 tonsurans of Cazenave, which is the Forrigo scutulata of Willan, the 

 Tinea tonsurans of Bazin, and the Triclwsis furfuracea of Erasmus 

 Wilson and Dr. Wood." The article from which we have quoted is 

 illustrated by some figures illustrative of the action of this curious 

 fungus, upon the hair. 



The only additional researches of moment known to me are those 

 by Dr. Thin and Dr. Gerlier. Dr. Thin has been noting the growth 

 of Tricophjton tomurans under the microscope. The only successful 

 method was by moistening the hairs with vitreous humour, when the 



