GROUPS OF PLANTS. 



21 



and profusely developed much like that of Phycomyces nitens 

 (Fig. 13, B). This mold is widely distributed, causing trouble 

 in the spoiling of many sugar- and starch-containing substances 

 in the household, including preserves, syrups, fruits, etc. In 



Fig. 13. B, richly branching mycelium (m) of the mold Phycomyces nitens show- 

 ing upright hyphae bearing sporangia (g). A, C, p, the common black mold Mucor 

 mttcedo. A, spoismgium with columella; C, germination of zygospore (z), with formation 

 of hypha (k), and sporangium (g); D, earliest stages in the development of a zygospore 

 the hyphal branches (b) showing adjoining ends (a) cut off by cross walls. — ^After Sachs. 



fact, a number of species of Mucor have the power of inducing 

 alcoholic fermentation in glucose-contaitting solutions. They 

 are also commonly found in many aqueous solutions of inorganic 

 chemicals as well as organic substances. Asexual spores are 



