126 



Mycologia 



At the conclusion of these studies, my own material will be 

 placed in the Carnegie Museum, Pittsburgh, and in the New 

 York Botanical Garden. This will be done in the hope that 

 other mycological workers who are not directly connected with 

 large public institutions will also deposit their material in institu- 

 tions where it will be available to future students. 



I am indebted to Dr. W. J. Holland, of the Carnegie Museum, 

 Pittsburgh, for assistance in making collecting trips in Pennsyl- 

 vania. My thanks are especially due to Dr. N. L. Britton for 

 the opportunity of examining the specimens in the herbarium and 

 consulting the literature in the library of the New York Botanical 

 Garden. The various members of the staff of the Garden have 

 very kindly and cheerfully rendered valuable service in the 

 preparation of this paper. 



Order Mucorales 



Saprophytic or parasitic fungi with well-developed mycelium, 

 the mycelium branched and unicellular. Reproduction sexual 

 (zygospores) and asexual (spores produced in sporangia or 

 conidia produced singly or in chains). 



Schroeter* recognizes five families, Mucoraceae, Mortierel- 

 laceae, Choanophoraceae, Chaetocladiaceae, and Piptocephali- 

 daceae. The total number of species for the whole world is less 

 than 150. Most of these are described from Europe. 



Family Mucoraceae 



Asexual reproduction by spores in sporangia with columella or 

 sometimes in sporangioles without columella. Sexual reproduc- 

 tion by zygospores formed on the mycelium or on aerial filaments 

 by the union of two copulating branches (gametes). 



Key to the Genera 

 I. Simplices 

 Sporangiophores simple, unbranched. 



Sporangiophores arising from stolons, sporangial 

 membrane not cuticularized. 

 Sporangiophores arising from the nodes of 



the stolons. i. Mucor. 



Sporangiophores arising from the internodes 



of the stolons. 2. Absidia. 



* Pflanzenfamilien : 123. 1892. 



