48 Marine Shells of the Western Coast of Florida 



valve deeply concave, ribbed; external ribs broad and separated by 

 narrow grooves; internal ribs with central sulcus. Interior white. 



P. raveneli, P. ziczac, and A. muscnstis are taken together in 

 five to seven fathoms. 



Genus AKQl'"'Kl'TKN"- P. Fischer, 1S86 

 Aequipeoten innscosus-*" (Wood) PI- 5, fig. 27 



Alt., 48; length, 46; diam., 18 mm. Surface spinose, rough; valves 

 uniformly colored; color range through brown, red, orange, lemon 

 and apricot shades; almost equivalve; ears unequal. Each valve bears 

 about 20 prominent ribs with finely ribbed interspaces; ribs closely 

 set with small, sharp, projecting scales; marginal scallops corres- 

 pond to ribs. Interior of valves ribbed and tinted with a pale shade 

 of exterior color. This Pecten is usually covered with a growth of 

 sponge, and adult individuals are usually attached by a byssus. 



Stormy blows often bring this Pecten to the beaches in great 

 numbers. 



Aeqnipecten gribbus^'' (Linne) PI. 6, fig. 28 



Alt., 50; length, 52; diam., 25 mm. Shell with family characters. 

 Color and pattern of bright or dull pinks and reddish purples on 

 white ground, variable; pure yellow specimens occur and some 

 blending of the two forms is seen. The upper valve is always more 

 gayly colored; interior delicately tinted in accord with exterior 

 coloration. Right — lower — valve deeper and umbonal elevation a little 

 higher than in left valve; about 20 rounded, radiated ribs, smooth 

 area below ears; concentric sculpture of fme laminations; deep mar- 

 ginal scallops formed by the ribs, interlock and ov^erlap. 



Taken only in the Gulf in more than three fathoms. Common on 

 the beaches after blows. 



Aequipeoten gibbus Irrsulians^^ (Lamarck) PI. 6, fig. 29 



Alt., 75; length, 75; diam., 34 mm. Shell with family charac- 



^■^ Lat., acquus, arrjui, equal. 



3^ Lat., muscus, moss, often covered with sponge. 



^^ Lat., gibbus, a hump. 



^** Lat., irradiare, to irradiate. 



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