INSECT SPERMATOGENESIS 623 



recalling the chromatoid body of other workers, seems thus 

 to be a rather unfortunate one, as it is quite improbable that 

 this body has anything whatever in common with the acrosome. 



Summary. 



1. The lepidopteran nebenkern passes through a series of 

 condensation phenomena which are essentially similar to those 

 previously described in Hemiptera, 



2. The structure of the chromophilic material is probably 

 that of a plate- work rather than a spireme. 



3. The central substance is developed in the nebenkern 

 exactly as in other insects. 



4. The Golgi bodies in all probability give rise each to a 

 small vesicle, these vesicles fusing gradually to form the 

 acrosome. 



5. As in other insects, the Golgi bodies are not directly 

 transformed in the building up of the acrosome, Ijut, after 

 giving rise each to its miniature acrosomal vesicle, they 

 pass back along the tail and are probably cast out of the 

 sperm along with other detritus in the concluding stages of 

 spermiogenesis. 



6. The essential parallelism existing between the formation 

 of the sperm in Lepidoptera and in other insects, especially 

 the Hemiptera, is particularly emphasized. 



Literature Cited. 



Bowen, R. H. (1920). — " Studies on insect spermatogenesis. I. The history 



of the cytoplasmic components of the sperm in Hemiptera ", ' Biol. 



Bull.', vol. 39. 

 — • — (1922a). — "Studies. II. The components of the spermatid and 



their role in the formation of the sperm in Hemiptera ", ' Journ. 



Morph.', vol. .37. 

 — ■ — (1922b).- — "Studies. III. On the structure of the nebenkern in the 



insect spermatid and the origin of nebenkern patterns ", ' Biol. Bull.', 



vol. 42. 

 — ■ — (1922c).- — "Studies. IV. The phenomenon of polymegaly in the 



sperm cells of the Family Pentatomidae '", ' Proc. Amer. Acad, of Arts 



and Sciences ', vol. 57. 



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