ALGAL AND FUNGAL PROTESTS 



45 



a little above the substratum. Mucors that produce 

 zygospores from the same thallus are termed homothallic, 

 those that do so only from different strains, heterothallic. 



S 



FIG. 9. MUCOR MUCEDO. M, mycelium bearing two conidiophores ; 

 C, sporangium with spores, two crystals more magnified, and end of 

 conidiophore with part of membrane and columella ; 8, 4 spores, the 

 two lower germinating ; z sp, stages in the formation of a zygospore ; 

 Z, zygospore, which has germinated by the promycelium ; pm, which 

 bears a conidiophore. Mainly after de Bary 



In M. mucedo, Fig. 9, the conidia are formed simulta- 

 neously in a sporangium, the wall of which may be beset 



