TURBINACEA. MOLLUSCA. PYRAMIS. 269 



Py'ramis stria'tula. 



Shell turreted, dingy-white ; whorls eight, nearly flat, toith 

 numerous fine, revolving lines ; upper whorls tapering rapidly ; 

 suture distinct. 



Figure 174. 



State Coll., No. 53. Soc. Cab., No. 2360. 



Py'ramis striatula, Couthouy ; Bost. Journ. J\"at. Hist., ii. 101 , pi. 1, f. G. 



Shell elevated, obelisk-shaped, thick, bluish-white, usually 

 having a dead, unpolished appearance ; whorls seven to nine, 

 nearly flat, distinctly separated by the suture, a few of the upper 

 ones tapering rather suddenly to an acute point, thus giving it an 

 obelisk shape ; marked with obvious lines of growth, sometimes 

 approaching to varices, and with from twelve to fifteen fine, reg- 

 ular revolving lines, diminishing in number towards the apex ; 

 aperture ovate, acute-angular behind ; outer lip sharp and simple, 

 without any sinus behind ; slightly turned outwards at base, as it 

 joins the regularly arched pillar margin. Length || inch, 

 breadth /^ inch, divergence 23°. 



First found by Mr. Couthouy in the stomachs of fishes caught 

 off Cape Ann. Several specimens have since been found, but it 

 is by no means common. 



I have employed the genus Py'ramis, not because I would adopt it, 

 but because I know not any estabHshed genus under which this shell 

 would come ; and do not wish to confuse, if I cannot correct. The 

 characters of the aperture are like those of the preceding species, but 

 the exterior has a ditTerent character. Its aspect is precisely that of a 

 shell sent me as Monoti'gma, Gray ; but I cannot find the plait on the 

 inner lip, from whence that genus derives its name. 



Genus ODOSTOMIA, Fleming. 



Shell conical, elongated; aperture ovate; lips disunited posteri- 

 orly, and sometimes produced anteriorly ; pillar with a tooth-like 

 fold; operculum horny , sub-spiral. 



