THE FUNGI WHICH CAUSE PLANT DISEASE 107 



simple or branched, erect sporangiophores; microsporangia clavate, 

 one-spored simulating conidia and borne in heads on the enlarged 

 apices of umbellately branched sporangiophores; zygospores as 

 in Mucoracae. 



A single genus, with three species. 



Choanephora infundibulifera (Curry) Sacc. and C. americana 

 A. Moll occur on blossoms in India and South America. 



A third species, C. cucurbitarum (B. & Br.) Thaxter, is the 

 cause of decay of cucurbits especially pumpkins, in the eastern 

 and southern states. ^^ 



Entomophthorales (p. 66) 



This order is predominately one parasitic on insects. Some 

 fifty species are known, only four of which are plant parasites. 

 Asexual reproduction is chiefly by conidia, apically borne and for 

 the most part forcibly ejected from their stalks at maturity. 



Key to Families of Entomophthorales 



Endozoic parasites (Insecta, Arachnoidea) . 1. Entomophthoracete. 

 Endophytic or saprophytic 2. Basidiobolaceae, p. 107. 



Basidiobolacese 



This family is characterized chiefly by its habitat. Septa are 

 numerous in the vegetative mycelium. 



Key to Genera of Basidiobolacese 



Intracellular parasites, the mycelium greatly 



reduced 1- Completoria, p. 108. 



Saprophytes, or parasites on higher fungi, 

 the mycelium well developed. 

 Conidia produced directly from an un- 

 swoUen conidiophore. Parasites on 



higher fungi 2. Conidiobolus. 



Conidia cut off from the apex of a swelling 



of the conidiophore. Saprophytic. . . 3. Basidiobolus. 



