PLATE 17 



1. 

 2. 

 3. 



4a, 

 5a, 

 6. 

 7. 



Cardlum muricatum Llnne. Sanibel, Florida. 35 mm. p. 49 

 Cardium robustijm Solander. Sanibel, Florida. 5 inches, p. 

 Cardium isocardium Linne. Florida. 3 inches, p. 48. 



49. 



4b. Laevicardlum mortoni Linn6. 

 5b. Trigonicardia medium Linn6. 

 Cardium cilia turn Fabricius. 

 Laevicardlum serratum Linn6. 

 8a, 8b, 8c. Papyridea spinosiam Meuschen. 

 9. Papyridea semisulcata Gray. 



Tarpon Bay, Florida. 1 

 Florida Keys. 3.5 inches 

 New England. 2 inches. 



Blscayne Bay, Florida. 



Florida. 8-16 mm. p. 

 Yamato, Florida. 10 mm. 



10a, 10b. Trigonicardia antillarum Orbigny. Bahamas. 20 mm. p 



p. 50. 



