38 COJNTRIBUTIOiNS 



CONCHIFERA BIMUSCULOSA. 



FAMILY TUBICOLARIA. 



GENUS TEREDO. Linnaeus. 



T. simplex. Plate 1. Fig. 6. 



Description. Shell thick, slightly curved, smooth exte 

 riorly, tapering. 



Observations. Possessing but two or three fragments of 

 the shell, it is impossible to make a perfect description. It 

 differs from the navalis (Lam.) in the substance of the shell 

 being thicker, and from the tibialis of Morton in being less 

 thick, the cavity of that shell being very small. It has no 

 transverse striee like the antenautce of Sowerby. 



In England one species only seems to have been ob 

 served, and that by Sowerby in the London Clay. In the 

 Tertiary tables of M. Deshayes we find five species, of 

 which three are from the Paris basin. Dr Morton has, 

 from the Chalk of New Jersey, described a fine species 

 the tibialis. 



