TURBINACEA. MOLLUSCA. TURRITELLA. 267 



GENUS TURRIT^LLA, LAM. 



Shell turretcd, elongated, spirally grooved, pointed; aperture 

 entire, rounded ; lips disjoined posteriorly ; operculum horny. 



TURRITE'LLA EROSA. 



Shell elongate-turret ed, pale-brown, composed of about ten 

 smooth, flattish whorls, sloping above to the suture, and grooved 

 with from three to Jive, obtuse, revolving furrows. 



State Coll., No. 38. Soc. Cab., No. 2286. 



Turritella erosa, COUTHOUY ; Bost. Journ. Nat. Hist., ii. 103, pi. 3, f. 1. 



Shell elongated-conical, turreted, pale horn-colored, with a 

 light reddish-brown epidermis ; whorls about ten, flattish, smooth, 

 sloping towards the suture, so that each whorl seems a little shelv- 

 ing over the succeeding one, and furrowed with from three to 

 five abrupt, revolving grooves, nearly as wide as the spaces be- 

 tween them. From five on the largest whorl, the number goes 

 on diminishing above ; the whorls at the apex are usually broken 

 off, and much of the summit is a good deal eroded. Lines of 

 growth are quite conspicuous in the grooves, but scarcely percep- 

 tible elsewhere ; aperture nearly circular ; lip sharp, meeting the 

 prolonged pillar, so as to produce a partial angle ; operculum 

 horny, multi-spiral. Length -J inch, breadth T V inch. 



Found in the stomachs of fishes caught in Massachusetts Bay. 

 It is usually found either incomplete, or much defaced and 

 broken. I have seen but one specimen containing the animal. 



It is quite different from any described species, unless it be T. Vir- 

 ginidna of Lamarck. His description is not sufficiently definite to 

 identify his shell with ours, and the character " basi annulo griseo-viola- 

 cescente notata," I have never found upon it. It bears a distant re- 

 semblance to the old Turbo terebra of English authors, but it does not 

 slope to a point so rapidly, and the sculpture seems to be from grooves, 

 and not from raised lines, as in T. terebra. 



