MUCORACEAE 35 



b. Wall of sporangium cutinized and persistent 



above, thin and diffluent below Pilobolae p. 



2. Columella lacking; zygospore in a dense weft 



of hyphae Mortierellae p. 



B. Conidia present in chains or clusters; represent- 

 ing sporangia 



1. Conidia in chains; zygospores arising usually 



from an outgrowth of the fused gametes Syncephalidae p. 



2. Conidia in clusters on spinose conidiophores; 



zygospores arising directly from the fused 



gametes Chaetocladiae p. 



Subfamily Mucorae 



A. Sporangia of one kind 



1. Sporangiophore repeatedly dichotomous Sporodinia 7:206; S 127, F 247 



2. Sporangiophore simple or branched but not 



repeatedly dichotomous 



a. Suspensors of the zygospore with spinose 



appendages at maturity 



(1) Appendages spreading Phycomyces 7:204; S 126, 



F 248; 2 



(2) Appendages loosely enclosing the zygo- 



spore Absidia 7:214; S 126, F 244 



b. Suspensors without appendages at maturity 



(1) Aerial mycelium present 



(a) Aerial mycelium stoloniferous Rhizopus 7:212; S 125, F 245 



(b) Aerial mycelium with many short 



spinose branches Spinellus 7:205; S 125, F 246 



(2) Aerial mycelium lacking 



(a) Sporangia single, terminal Mucor 7:190; S 124, F 250; 2 



(b) Sporangia clustered, lateral 



X. Sporangia globoid; columella cylindric 



to conic Circinella 7:il5, S 125, F 244 



y. Sporangia piriform; columella hour- 

 glass-like Pirella 7:216; S 125, F 243 



B. Sporangia of two kinds, primary and secondary 



1. Both kinds of sporangia with columella Dicranophora 11:240; S 128, 



F 254 



2, Primary sporangia with, secondary without 



columella Thamnidium 7:211; S 127, 



F 256; 2 



Subfamily Pilobolae 



A. Sporangia seated on a large vesicle, thrown off 



at maturity Pilobolus 7:184; S 129, F 251; 2 



B. Sporangia not on a vesicle and not thrown off at 



maturity Pilaira 7:184; S 129, F 253 



Subfamily Mortierellae 

 A. Sporangia present 



1. Sporangia arising directly from normal hyphae 

 la. Sporangiophores erect, branches long-atten- 

 uate Mortierella 7:220; S 130, 



F 265; 2 



