CH. XV. j 



MOULD-FUNGI. 



141 



of the mycelium at their ends or laterally at a septum produce 

 by division a series of spherical or oval conidia- spores, about 

 O r 007 to O'Ol mm. long. These ultimately become isolated, and 

 then germinate into a short cylindrical filament, which sub- 

 divides by transverse septa into a series of cylindrical cells ; 



FlO. I'M. OlDItTM LACTI3. 



Mycelium and spores. 



these by continued growth and division give origin to the 

 ordinary septate branch-hyphse. The formation of conidia 

 proceeds at the ends of these in the same manner as before. 

 The oidium lactis forms a whitish mould on milk, bread, paste, 

 potato, &c. 



Favus, Herpes tonsurans, and Pityriasis versicolor of man 

 and animals, are, according to the researches of Grawitz, 1 due 

 to a fungus in morphological respects identical with oVdium 

 lactis. In favus it is known as Achorion Schoenleini, in Herpes 



1 Virchow'a Archiv, vol. Ixx. p. 560. 



