20 



MORPHOLOGY AND CULTURE OF MICROORGANISMS. 



greatly with the species or even- with races used, approaching in some 

 species the efficiency of the more active yeasts. 



THAMNIDIUM. Of related genera, Thamnidium differs from Mucor 



FIG. 4. Penicillium expansum, Link, a, b, f, Branching and arrangement of 

 branches of conidial fructification (XQOO) ; c, d, e, conidiiferous cells and conidial chains 

 (Xgoo); g, h, j, k, /, sketches of fructifications (X 140); m, n, o, germination of conidia 

 (Xgoo); r, s, sketches from photographs showing in 5 loose aggregations of conidio- 

 phores beginning to develop into zonately arranged coremia, in r a coremium i mm. in 

 height. (From Bui. 118, Bureau of Animal Industry, U. S. Dept. Agriculture). 



in the production of two kinds of sporangia. The terminal sporangium 

 of a fruiting hypha resembles that of Mucor; the secondary or accessory 

 sporangia which are borne upon side branches of the sporangiophores 



