174 



PHYCOMYCETEAE 



mophthora). The zygospore is thick-walled. In many species similar 

 spores are formed parthogenetically, the azygospores. 



Family Entomophthoraceae. Usually only one family is recognized 

 in this order: the Entomophthoraceae. 



Conidiobolus is saprophytic or weakly parasitic on the fruit bodies of 

 higher fungi and on certain insects. Its asexual spores are conidia, not 

 dividing internally into sporangiospores. The branching mycelium is 

 divided by septa into multinucleate segments. The spherical conidia are 

 shot off in the manner characteristic of the family. Sexual reproduction 

 occurs by the union of adjacent cells of unequal size in the same hypha 

 or by contact of two hyphae. The contents of the smaller gametangium 

 are cut off from the supporting cell (or suspensor) by a septum. They pass 

 through a pore into the female cell within which the thick-walled zygo- 

 spore becomes mature. On germination it produces a conidiophore or 

 mycelium. (Fig. 60.) 



Basidiobolus is most frequently found growing saprophytically on 

 the excrement of frogs, lizards, etc. It has been isolated by van Overeem 



i 



'■'A 



Fig. 6]. Entomophthoralcs, Family Entomophthoraceae. Asexual reproduction. 

 (A-F) Basidiobolus ranarum Eidam. (A) Developing conidiophore. (B) Apex of 

 mature conidiophore. (C-E) Development of conidium into sporangium in stomach 

 of frog. (F) Spores set free from sporangium. (G, H) Entomophthora muscae (Cohn) 

 P'rcscnius. (G) Grouj) of conidiophores. (H) Single conidiophore. (A, B, G, H, after 

 Thaxtcr: Mem. Boston Soc. Natural History, 4(6):133-201. C-F, after Levisohn : JaAr6. 

 wiss. Botan., 66(3) :5 13-555.) 



