MURAWSKI ET AL.: GROWTH OF OCEAN QUAHOG, ARCTICA ISLANDICA 



Figure 1.— Ocean quahog shells used 

 for growth analyses taken near lat. 40° 

 25'N. long. 72°24'W, in the Middle At- 

 lantic Bight, (a) Specimen 65 mm. shell 

 length, marked during July-August 

 1978 and recaptured during August 

 1979. Arrow indicates external growth 

 band formed during the interval be- 

 tween marking and recapture, (b) Ar- 

 row indicates shell growth of a 68 mm 

 specimen from July-August 1978 to Au- 

 gust 1979 with periostracum removed, 

 (c) Arrows indicate positions of most re- 

 cently formed external growth bands on 

 small individuals from August 1979 

 (right, 43 mm) and February 1980 (left, 

 45 mm) samples. 



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