742 ANALYSIS OF CONTINENTAL JOURNALS. 
to the paper detailing his original investigations as one of 
such particular interest to the comparative pathologist as to 
warrant us in giving a translation of it in this journal. This 
we now have much pleasure in doing, adding also, as a sup- 
plement to the principal memoir, which appeared in the 
Recueil for 1869, the later observations of this distinguished 
veterinary teacher, which were subsequently published in the 
Lyons Journal de Medecine Veterinaire. 
The disease which has been the subject of his special 
study is that vulgarly known in human pathology as scald- 
head , and technically as tf Favus or e Tinea favosa ,’ with its ac- 
cidental varieties Porrigo larvalis , Porrigo lupinosa , and Por- 
rigo scutulata. It depends upon the presence of a cryptogamic 
fungus named the Achorion Schonleinii , after Schonlein, who 
first suggested that the yellow favus crusts in the two latter 
varieties of the malady were due to a vegetable production. 
The primary seat of the parasite, according to Aitken, is in 
the depth of the hair follicle, outside the layer of the epithe- 
lium which covers the root of the hair, and which forms the 
‘ inner root sheath 5 of Kolliker. By using a concentrated 
solution of liquor potassce, to make the parts transparent, the 
fungus may be observed with the microscope in the follicle 
round the hair at the place where it passes through the 
epidermis. A second form of the disease in man is that in 
which the plant is found in depressions on the surface of the 
skin, forming the yellow honeycomb-like masses which gave 
the specific nam e favus to the disease, and which, from their 
frequent buckler-like shape, suggested the term f scutulata.’ 
A cuticular elevation is seen, beneath which is a small favus. 
When the cuticle is raised a drop of pus sometimes issues; 
hence the error of those who have considered this disease 
always pustular. Generally, however, there is no pus or 
liquid of any kind ; the plant grows, and the cuticle over it 
(supposing it has not been forcibly detached) finally separates, 
leaving the favus exposed to the air. A third form of the 
disease is that in which the fungus attacks the nails, and 
occurs, for the most part, in those who have been long 
affected with the favus of the hair follicles, the fungus taking 
root and germinating beneath the nail. After the spores 
liave commenced to germinate between the superficial and 
deep epidermic layers, the nail becomes thickened over the 
affected part, and its colour becomes gradually more and 
more yellow, owing to the favus matter shining through it. 
As the fungus increases in growth, it gradually presses on 
the nail, rendering its longitudinal striae very evident, and 
ultimately leading to the formation of fissures in it. As the 
