48o MICRO-ORGANISMS AND DISEASE [chap. 



conidia germinate into shorter or longer cylindrical filaments, 

 which by subdivision form septate mycelial hyphse. These 

 and their branches give origin in their turn to spherical or 

 oval spores or conidia. They, as well as the hyphse, differ 

 in size in the various species. 



Malcolm Morris and G. C. Henderson,^ on the other hand, 

 maintain that by artificial cultivation of the spores of 

 Trichophyton in the substance of gelatine-peptone, at tem- 

 peratures varying from 15° to 25° C, these grow into 

 branched septate mycelial filaments, which by their mode of 

 fructification are seen to be identical with the mycelium of 

 Penicillium. Compare also with Babes.^ 



{b) Aspergillus. — Some of the branches of the mycelium 

 of this fungus assume an upright position, are thicker and 

 not at all, or only slightly, septate, and at their end form 

 flask-shaped enlargements, from which grow out radially 

 short cylindrical cells — basidia , and these again at their 

 distal or free ends produce chains of spherical spores or 

 conidia. This is a very common mould, and according to 

 differences in the colouration of the mycelium and spores is 

 subdivided into different species : A. glaums, candidus, 

 flavescens, fumigatus, is'c. 



Besides this mode of spore-formation (asexual), there is 

 another (sexual), which according to De Bary consists in 

 this : some terminal branch of the mycelium becomes 

 twisted like a spiral, this is considered the female organ of 

 fructification or carfogonium ; from the same thread branches 

 grow towards the carpogonium ; one of these branches 

 becomes fused with the terminal portion of the carpogonium 

 called the ascogonium, while the others — the pollinodia — 

 branch and surround the carpogonium like a capsule : the 



^ Journal of Ihe Royal Microscopical Sociely, April 11, 1883. 

 ' Archives de Physiologie, 8, 1883, p. 466. 



