199 St. Maurice and Ci<aiborne Pra.ECYPODA 199 



Teredo simplex Lea, PI. 59, Fig. 16 



T. simplex Lea, Cont. to Geol.. Dec. 1833, p. 38, pi. r, fig. 6. 



Lea's oris^inal descripfion. — vShell thick, slightly curved, smooth ex- 

 teriorly, 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 the shell being very small. It 

 has no transverse stride like the antenaiitce of Sowerby. 



We have noted various, somewhat larger tubes of this Clai- 

 bornian bluff t3^pe, but none in which the true shell was pre- 

 served. 



Type. — No. 5019* ,Lea Coll. Phila. Acad. 



Horizo7i. — Claiborne Eocene. 



Teredo Simplexopsis de Gregorio, PI. 59. Fig- 17 



Teredo simplexopsis de Greg., Mon. Faun. Koc. Ala., i8qo, p. 236, pi. 

 38, figs. 26, a, b. 



Gregorio' s original description. — Testa tubulosa, cylindrica, potius 

 tenuis, fere recta ; extremitate clausa, rotundata, non autem dilitata. 



Au pr^alable, j'avais r^fere cette espece a la Teredo si?nplex Lea ; 

 mais en suite, ayant examine quelqueexemplaires de cette derniere espece, 

 je me suis apercuqu'ils appartenaient au genre Serpida. Notre espece est 

 beaucoup moins 6paisse ; son interieur est moins restrinct. La coquille 

 garde encore un certain couleur rougeatre. 



Regarding this species Dall remarks (Trans. Wag., Ill, p. 

 813) that de Gregorio has identified what he (G.) regards asa 5rr- 

 pula tube from Claiborne, with Lea's species, and for the true 

 Teredo tubes which occur in the Claiborne sands has proposed 

 the name of Teredo simplexopsis, w^hich probably may have to 

 be regarded as a synonym of Teredo simplex, while the Scrpvla 

 will need a new name. 



*No, 5020 is a more irregular form of like dimensions. 



