14 GO^^CBYLIX—DITHYRA. 2. 



mantle, or by an outer cuticle or membrane which invests the whole 

 animal; and this fold perishes with the animal, leaving the valves 

 to fall asunder, or to be connected by a mere film. 



nivalis Teredo volvis postici auriformihus , altera denticulo curvo marginali 



supra dentem. 

 Shell with the valves ear-shaped behind, one of them with a curved 

 denticle on the margin above the teeth. 

 Tab nost. 2. fig. 1 to 3. 

 Teredo navalis. Linn. Syst. Nat. p. 1267. 

 Gmelin. Syst. p. 3747. 

 Thirton, Linn. Syst. iv. p. 609. 

 Pennant, Brit. Zool. iv. p. 367. 

 Montagu, Test. Brit. p. 27 and suppl. p. 7- 

 Home, Phil. Trans. 1806, p. 276, tab. 12 and 13. 

 Turton, British Fauna, p. 202. 

 Linn Trans, viii. p. 249. 

 Donovan, Brit. Shells v. tab. 145. 

 Dorset Catal. p. 60, tab. 18. fig 12. 

 Dillwyn, Descript. Catal. p. 1089. 

 Turton, Conch. Diet. p. 183. 

 Serpula Teredo. Da Costa, Brit. Conch, p. 21. 

 Mus nost. In timber exposed to their action in salt water. 



Shell about three quarters of an inch in diameter, with the valves 

 triangular and forming a circular hemisphere when closed to- 

 gether, elegantly striate in various directions, each with a trian- 

 gular projection in front bending a little inwards, and with an 



