FISHERY BULLETIN: VOL. 82, NO 2 



ferentiated condition (Table 1, Fig. 7a, b). Gonadal 

 tubules were of small diamater, few in number, 

 and surrounded by an abundant loose vesicular 

 connective tissue. Gonia embedded in the germi- 

 nal epithelium lacked definite cellular structures 

 for sex determinations. The lumina of tubules 

 were empty. 



Sex determinations were possible for 97 

 quahogs, but in most (69) the gonads appeared to 

 be in an intermediate stage and not fully devel- 

 oped. These latter tissues were separated into two 

 categories: Those with either sparse or moderate 

 tubule development. 



Differentiated gonads with sparse tubule devel- 

 opment were characterized by a limited number of 

 gametogenic cells, as well as a limited number of 

 tubules. The 16 male tissues examined were pro- 

 ducing a few sperm; the 4 female tissues examined 

 were producing a few oocytes. Abundant loose ve- 

 sicular connective tissue occurred between the 

 widely spaced gonadal tubules. In males, sper- 



matogenic cells at the germinal epithelium were 

 about one layer thick, but were absent in portions 

 of the epithelium (Fig. 8a, b). Some sperm were in 

 close contact with the spermatogenic cells and a 

 few were scattered in the lumina of tubules. In 

 females, the few small oocytes occurred at the 

 germinal epithelium, none were in the tubule 

 lumina, and all were in an early developmental 

 stage (Fig. 8c, d). 



For differentiated gonads with moderate tubule 

 development, 39 males examined were producing 

 sperm, while 10 females examined were producing 

 oocytes. The gonadal tubules were more numerous 

 than in gonads of sparse tubule condition, and 

 some exhibited an expanded alveolar condition. 

 Loose vesicular connective tissue clearly sepa- 

 rated the tubules. In males, several layers of sper- 

 matocytes proliferated from the germinal 

 epithelium with some sperm forming a fringe ex- 

 tending toward the empty lumina; however, por- 

 tions of the germinal epithelium in some tubules 



TABLE 1. — Gonadal condition relative to age. sex. and size of three categories of ocean 

 quahogs. An tua islandica — sexually immature, intermediate, and mature — off Long 

 Island. N.Y.. late July-early August 197s. M = male; F = female. 



'The tissues of a 21.1 mm. 3-yr-old clam were too poorly prepared for examination 



260 



