266 NEW FOSSIL SHELLS 



The peculiar lenticular form of this shell will at once distinguish it from all our other 

 fossil species. The only one, indeed, to which it, bears any resemblance is the T. 

 reclusus. From this it differs chiefly in size, umbilicus, and columella. 



T. TORQUATUS, PL. 37. FlG. 84. 



T. testa conicd, acuminatd, crassd, politd } perforatd, crenulato-costatd; spird sub-conicd, depressiusculd, obtusd; suturis 

 parvis; anfractibus quatuor, sub-convexis; costis transversis, quatuor, noduliferis; anfractu ultimo acute angulato, carinato; 

 basi qrebre et profunde striatd; pcrforatione parvd; aperturd quadr angular i. 



Shell conical, acuminate, thick, polished, perforate, crenulately costate; spire somewhat conical, rather depressed; 

 obtuse; sutures small; whorls four, nearly flat; costas transverse, four, noduliferous; last whorl acutely angular, cari- 

 nate; base closely and profoundly striate; perforation small; mouth quadrangular. 



Length .13. Breadth .12 of an inch. 



Remarks. The carina on the periphery of the last whorl is round and polished. 

 There are three large, and one small nodulose costee, the small one being next to the one 

 nearest the upper suture. 



This much resembles the T. armillus, herein described, but may be readily distin- 

 guished from that shell by its umbilicus, more ovate shape, and more striate base. 



T. ARATUS, PL. 37. FIG. 85. 



T. testa ovato-conicd, crassd, politd, imperforatd, costatd; spird dcpressd, sub-ovatd, obtusd, ad apicem Icevi; suturis parvis, 

 linearibus; anfractibus tribus, sub-convexis; costis transversis, tribus, magnis, sub-noduliferis ; anfractu ultimo angulato, 

 costis quatuor ; basi sulcatd; aperturd rotunda. 



Shell ovately conical, thick, polished, imperforate, costate; spire depressed, sub-ovate, obtuse, smooth near the 

 apex; sutures small, linear; whorls three, slightly convex; costae transverse, three, large, sub-noduliferous; last whorl 

 angular, with four ribs; base sulcate; mouth round. 



Length .08. Breadth .08 of an inch. 



Remarks. In the only specimen of this shell now before me, the two upper ribs are a 

 little nodulous, while the two lower ones are smooth. As this is a variable character, it 

 is probable that they may all be nodulous in other specimens. The additional one on 

 the last whorl is almost large enough to be called a carina. The base is closely and 

 deeply grooved. The mouth is perfectly round. 



This shell is somewhat similar to the T. armillus, herein described, but is sufficiently 

 distinguished by its more ovate form and round mouth. 



T. RUFFINII, PL. 37. FIG. 86. 



T. testa conicd, crassd, costatd, imperforatd ; spird elevatd ; suturis minimis, linearibus- ; anfractibus , inferne carinatis 



et sulcatis, superne concavis et costatis; costis transversis, tribus, noduliferis, altcrnantibus striis minutissimis ; anfractu ultimo 

 ungulato, bicarinato, carina superiore sub-crenulatd ; basi Icevi; aperturd transversd, quadrilaterali; columelld rotundatd, lined 

 impressd marginatd. 



Shell conical, thick, costate, imperforate; spire elevated; sutures very small, linear; whorls , carinate and 



sulcate below, concave and costate above; costse three, transverse, noduliferous, alternating with very minute striae- 

 last whorl angular, bicarinate; upper carina sub-crenulate; base smooth; mouth transverse, -quadrilateral; columella 

 rounded, margined by an impressed line. 



Length . Breadth .33 of an inch. 



Remarks. The edge of the last whorl has two carinse, or perhaps, more strictly speak- 

 ing, a large carina with a deep groove in its centre. On the superior whorls, the upper 

 carina and groove are alone visible. The transverse stria3 are almost invisible to the 



