PORTER: REPRODUCTIVE CYCLE OF MYA ARENARIA 







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•• •. 



'*.->*■ 

 .*•*-. 



f". 





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4 



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rx 



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tkt/ 



Figure 2. — Gonadal stages of the soft-shell clam, Mya arenaria , at Skagit Bay, Wash, a) Spawning male (100 x ), 6 Aug. 1971. The 

 follicle cells reappear as spawning progresses, b) Spent male ( 100 x ), 8 Sept. 1972. c) Inactive female (100 x ), 12 Oct. 197 1 . Follicle 

 cells containing the typical female inclusions fill the alveoli, d) Early active female (145 x ), 3 Mar. 1972. The primary ovocytes 

 begin enlarging forming stalked ovocytes, e) Active female (136x), 8 May 1972. The follicle cells and their inclusions have 

 disappeared, f) Late active female (240 x), 14 June 1972. The nucleolus and amphinucleolus of the ova have appeared, but most 

 ova are still attached to the basal membrane of the alveoli. 



651 



