MUCORALES 265 



the hasp; conidia unicellular, slohose, orhinulato, bonio 

 apically on simple or ))ranchcd conidiophores; zygospore 

 enveloped at maturity in a thick layer of closely woven 

 hyphae. 



1. Mortierella, p. 265 



2. Sporangiophore procumbent, of uniform diameter through- 

 out, sympodially branched. 



2. Herpocladium, p. 268 



B. Sporangiophores arising from a liighly specialized, stout, creeping 

 fertile hypha, and successively produced as buds behind its 

 advancing tip. 



3. Dissophora, p. 268 



II. Sporangium absent, replaced by mono- or bispored sporangiola which 

 are borne terminally and sometimes also laterally on short branches 

 which radiate from fertile intercalary segments of the mycelium. 



4. Haplosporangium, p. 268 



1. Mortierella Coemans (1863: 536). 



Mycelium procumbent, within the upper layer of the medium 

 or forming a tightly appressed weft over its surface, not typically 

 aerial ; sporangiophores erect, simple, or variously and character- 

 istically branched, usually tapering to a delicate hair-like tip 

 just below the sporangium, and more or less swollen or ventricose 

 downwards; sporangia globose, lacking a columella, provided with 

 a delicate wall which disappears soon after reaching maturity, 

 leaving only a remnant at the pointed apex of the sporangiophore ; 

 conidia (by several writers here termed stylospores) unicellular, 

 globose, echinulate, occurring at the tips of simple or branched 

 aerial conidiophores in various species, and recalling the mono- 

 spored sporangia of Haplosporangium decipiens; zygospores 

 enveloped at maturity in a thick layer of closely woven hyphae, 

 which arise immediately below the gametangia and tend to 

 obscure the conjugation process (Fig. 95). 



The species of the genus, about thirty in number, are for the 

 most part saprophytes on dung, humus, fruit bodies of higher 

 fungi, etc. A few are facultative parasites. They are known 

 chiefly from Europe, the genus having received little attention 

 in America (Kauffman, 1920). The best taxonomic treatment 

 of the group is that of Dauphin (1908). 



Thaxter (1922: 291) has brought together under the pro- 

 visional name Endogoneae several as yet imperfectly understood 

 genera which show in certain respects indication of relationship 

 with Mortierella. The genera included are Endogone Link, 

 {Glomm Tulasne), Sphaerocreas Sacc. & Ellis, Sclerocytis 



