60 bulletin: museum of comparative zoology. 



B. Material and Acknowledgments. 



Phrynotettix magnus belongs to the subfamily Oedipodinae of the 

 orthopteran family Acrididae. The specimens that furnished the 

 basis for this investigation were collected in 1907 near the Santa Rita 

 Mountains of southern Arizona, by a collecting party from the Uni- 

 versity of Kansas. The testes were dissected out and fixed in Flem- 

 ming's stronger solution. Sections were cut 6-12 micra thick and 

 stained either by Heidenhain's iron-haematoxylin, or by Flemming's 

 tricolor, method. Material from thirteen animals was available and 

 consisted partly of the slides used by Miss Pinney as the basis of her 

 paper of 1908, partly of other slides prepared in Dr. McClung's labora- 

 tory, and lastly of material sectioned and stained by the writer. 



The work was begun in 1911 at the University of Kansas under 

 the direction of Prof. C. E. McClung, to whom I am indebted for 

 the material used and for advice and kindly interest throughout. The 

 greater part of the work was done at Harvard University during the 

 years 1912-1915 under the direction of Prof. E. L. Mark, to whom I 

 owe my warmest thanks for valuable criticism and suggestions and 

 for sympathetic interest at all times. I am also indebted to Miss 

 Eleanor Carothers, formerly a fellow student, for some collaboration, 

 especially with reference to the so-called "plasmosomes." 



II. OBSERVATIONS. 



A. Outline of spermatogenesis: Nomenclature. 



a. Introductory. 



There is some confusion in the literature on maturation in regard 

 to the use of the terms applied to the various steps and processes in 

 the history of germ-cells undergoing development into gametes. This 

 is due in part to differences in the details of the processes in the various 

 forms investigated, and in part to different interpretations of similar 

 stages by different authors. It therefore seems necessary, or at least 

 expedient, to explain the terms that one wishes to use in description. 

 A brief outline of acridian spermatogenesis follows, in connection with 

 which the nomenclature employed will be explained. In addition, 



