FAVUS. 



^29 



Pathologij. — Tlie disease depends upon a cryptogamic fungus, 

 named the . acliorion Sclionleinii, after Sclionlein, who was the 

 first to suggest that the yellow crusts were constituted by a 

 vegetable parasite. The primary seat of the parasite is in the 







Fig. 142. 



Fig. 143. 



Fig. 142. — Branches of achorion Sclionleinii in an early stage of devel- 

 opment, growing from molecular matter, and mingled with epidermic 

 scales, from a very minute favus crust. 



Fig. 143. — Fragments of the branches more highly developed, with 

 numerous sporules and molecular matter, from the centre of an advanced 

 favus crust. — (Bennett.) 300 diam. 



depth of the hair follicle outside the layer of the epithehum, 

 which covers the root of the hair, and which forms the " inner 

 root sheath of Kolliker." — (Aitken.) 



By making their sections of the favus crusts, and treating 





t^s^vl 



Fig. 144. Thalli, mycelia, and sporidia of the achorion Schonleinii, 



showing the mode of reproduction. -(Bennett.) 800 diam. 



