206 PROCEEDINGS OF THE AMERICAN ACADEMY. 



herein cited ; to Prof. E. C. Jeffrey for photographing certain of the 

 plates; but above all, to Prof. R. Thaxter, who, besides being the one 

 under whom this research has been prosecuted and to whom a pupil's 

 thanks are due for advice and encouragement, has placed at the writer's 

 disposal his mounted specimens and tube cultures of forms of the Muco- 

 rineae which have been accumulated during his extensive investigations 

 among the lower fungi. 



Thanks are due to the following for material : Prof. George Klebs ; 

 Prof. H. M. Ward, and Dr. R. H. Biffen ; Prof. O. Brefeld, and Dr. 

 R. Falck; Prof. D. H. Campbell; Prof. F. Cavara ; Prof. P:d. Fischer; 

 Prof. P. Vuillemin ; Mr. Robert M. Grey ; Mr. C. S. Leavenworth ; Mr. 

 J. B. Rorer; Mr. J. J. Wolfe; and to numerous others both in America 

 and Europe for similar favors, especially in connection with the Rhizopus 

 table (p. 263). 



Contents. 



Part I. Page 



Introduction 207 



Historical Review of the Theories relating to Zygosporic Reproduction in 



the Mucorineae 214 



Citation of Species from which Zygospores have been reported 220 



Part II. 



Introduction 245 



Heterothallic Forms 245 



Rhizopus nigricans 246 



Mucor Mucedo 271 



Pliycomyces nitens 281 



Absidia caerulea 284 



Mucor N 285 



Mucor III 286 



Mucor IV 287 



Mucor V 288 



Mucor VI 289 



Summary of Heterothallic Forms 289 



Homothallic Forms . 290 



Sporodinia grandis 291 



Spinellus fusiger 293 



Mucors I and ii 293 



Zygorhynchus Moelleri 297 



Dicranophora sp 300 



Summary of Homothallic forms 301 



Hybridization 303 



Summary 312 



BlULIOGRAPUY 314 



