FISHERY BULLETIN: VOL. 72, NO. 3 



Figure 1. — Gonadal stages of the soft-shell clam, Mya arenaria, at Skagit Bay, Wash, a) Inactive male (160x), 22 Sept. 1972. 

 Follicle cells with inclusions fill the alveoli, b) Early active male ( 160 x ), 17 Feb. 1972. Proliferation of the primary spermatocytes 

 is visible along the basal membrane of the alveoli, c) Active male (250x), 30 Apr. 1971. Spermatids begin aligning in radial 

 columns toward the central lumen of the alveoli. A few sperm balls are visible near the periphery of the alveolus, d) Late active 

 male ( 250 X), 14 May 1971. e) Ripe male (250 x), llJune 1971. The sperm are aligned in radial columns, their tails projecting into 

 the central lumen, f) Early spawning male (250 x), 1 June 1972. A single row of follicle cells containing inclusions forms at the 

 basal membrane of the alveoli. 



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