ZYGOMYCETES 



97 



Parasitella simplex (Burgeff, 1920) forms a special storage organ. Behind 

 the cup, the hypha swells into a sac which is abjointed and surrounded by 

 a thick wall (Fig. 56, d, 2) formed like the zygospore walls. As the proc- 

 esses in the formation of the cupping cells in these two genera are remi- 



ffhrasilella 





 



3 



*«p— ° 



, ■ pVl i mi» : 



* ' 1 ®^ *W\ J c 

 ^■^ ° 







c 



Chaetocladiam 



Sjtifi- 4- 



Fig. 56. — Diagram in one plane of the development of Parasitella and Chaetocladwm. The 

 nuclei of the parasite are shaded. S. Inf., secondary infection. (After Burgeff, 1924.) 



niscent of plasmogamy and as their parasitism is limited sexually, in that 

 Parasitella + only parasitizes Absidia glauca — and Parasitella — only 

 Absidia glauca +, Burgeff considers this type of parasitism to have arisen 

 as a sexual function, perhaps an attempt at hybrid copulation. 



As resting conditions, thick- walled gemmae are known (Fig. 54, 5), 

 in Mucor sphaerosporus the mycelium may form true sclerotia. The 



