CONTRIBUTIONS FROM THE ZOOLOGICAL LABORATORY OF THE 

 MUSEUM OF COMPARATIVE ZOOLOGY AT HARVARD COLLEGE, 

 E. L. MARK, DIRECTOR. — No. 190. 



MATURATION STAGES IN THE SPERMATOGENESIS OF 

 VESPA MACULA TA Linn. 



By E. L. Mabk and Manton Copeland. 



Received May 27, 1907. 



In a brief account of spermatogenesis in the honey bee, published 

 four years ago, Meves (: 03) showed that, contrary to the condition thus 

 far observed in the animal kingdom generally, the maturation divisions 

 of the primary spermatocjrtes resulted in the production of two "Rich- 

 tungskorper " and a single functional cell, instead of four functional 

 spermatozoa. The first of these two bodies was composed exclusively 

 of cytoplasm ; the second, however, was nucleated. Our observations 

 on the germinal cells of the honey bee published last year (Mark and 

 Copeland, = 06) confirmed in a general way those of Meves, differing 

 from his, however, in numerous details. 



Meves states in a very few words in the paper cited that in the 

 spermatogenesis of Vespa germanica the first maturation division re- 

 sults, as in the honey bee, in the formation of a non-nucleated bud 

 of cytoplasm, but that the second gives rise to two cells of equal size, 

 both of which are metamorphosed into spermatozoa. 



Having been able to collect, prepare, and examine the male germinal 

 cells of Vespa maculata Linn., we will set forth briefly in this paper 

 some of our observations. 



At the end of the growth period following the last spermatogonial 

 division, the cells (compare Figure 1) closely resemble those of the 

 honey bee. The nucleus is relatively large, and the chromatin is for 

 the most part aggregated into a single, somewhat irregularly shaped 

 body. Lying against the cell membrane are the remnants of the inter- 

 zonal filaments of the preceding cell division, which have become 

 metamorphosed into a rather homogeneous mass, to which we have 

 given the name interzonal body (Figure 1, ^')- 



