PLATE 27 



Teredo navalls Llnne. Borings in timber, p. 70. 



Petrlcola pholadiformis Lamarck. Long Island, New York. 2.25 inches, p. 56. 



Pholas campechiensis Gmelin. 3.5 inches, p. 68. 



Barnea maritima Orbigny. Gulf of Mexico. 35 mm. p. 69. 



Zirfaea crispata Linn6. Scituate, Massachusetts. 2 inches, p. 69. 



Barnea costata Linne. Cape Sable, Florida. 6 inches, p. 69. 



Zirfaea crispata Linn6. Sanitel, Florida, p. 69. 



