70 



EAST COAST MARINE SHELLS 



IIARTESIA C/JIIBAEA Orbigny. Shell broadly 

 wedge-shaped, inflated at anterior end 



which has fine 

 wavy lines; pos- 

 terior half marked 

 by small concen- 

 tric lindulations 

 and growth lines. 

 Length 9-17 mm. 

 In 1904 

 C. W. Johnson 

 collected this 

 shell in soft ar- 

 tificial lime- 

 stone off the wa- 

 ter battery in St. 

 Augustine. It has 

 only been record- 

 ed from limestone, 

 or boring Into oth- 

 er shells, while 

 the other Martesl- 

 as are more fre- 

 quently taken in wood. The illustrations 

 of the three species are from Johnson's 

 drawings. 



Fig. 38 



New York to Florida; Texas; Cuba 



Fig. 38 



Martesla 



caribaea 



i 



Family Teredidae 



Shell globular, open in front and 

 rear; valves three lobed with one trans- 

 verse furrow. 



Animal worm-like, foot sucker-like; 

 siphons very long, united almost to end. 



GENUS TEREDO Linne 1758 

 (SHIP WORIVIS) 



TEREDO NAVALIS Linn6. Usually one foot 

 long but sometimes over two. It destroys 

 soft v/ood quickly, even oak and teak do 

 not escape, therefore is one of the great- 

 est enemies to industrial mankind. The 

 "ship Teredo" invariably bores in the di- 

 rection of the grain unless it meets the 

 tube of another Teredo or encounters a 

 knot. 



In the Pacific another Teredo bur- 

 rows in the husks of floating cocoanuts 

 and other woody fruits. The tube of the 

 giant Teredo arenaria attains a length of 

 o feet and a diameter of 2 Inches; a cross 

 section presents a radiating prismatic 

 structure. 



PI. 27, Fig. 1 



Arctic Ocean to Florida, Europe 



DIPLOTHYRA Tryon 



This genus is allied to Martesla , but differe in the double or 

 divided dorsal valve. Shell short, ovate, divided in the middle by 

 an oblique impressed line, posterior to which the surface is covered 

 •with growth lines only, but anteriorly it is finely and sharply trans- 

 versely sculptured and obsoletely radiately ribbed in some specimens. 



The umbonal plates are generally much distorted so that no par- 

 ticular form can be traced throughout all specimens though the more 

 perfect approach to that depicted in the magnified figure above. 



Length: 6"; height and breadth: /;" ; habitat: Tottenville, Staten 

 Island, burrowing in oyster shells. "The shells were all dead, and 

 I have found as yet no evidence of the oysters being imported ones." 



Specimens in collection of National Museum from Philadelphia; 

 Crisfield, lid.j Staten Island; St. Augustine, Fla.; It^^le of Palms 

 (Long Island); South Carolina; liorehead City, N. 3. 



Quoted from : Tryon, Geo. "'V. 1863, "Description of a new genus 

 and species of Philadidae." Proceedings of the Academy of Nat. ocience 

 of Philadelphia, 1B62, 2d Series, Vol. VI, pp. U*9-L51. 



