NOBTHTA. 



fasciole ; aperture rhombo-ovate, oblong; labmm entire, not sinuous, 

 smooth within ; columella inversely sigmoidal, concave near the middle, 

 with a very thin callous deposit and with a revolving linear plait in front. 



Tertiary, I'/ifful 7///rx ml Fra. 



Dr. Gill refeis his genus to the family Bnccinida3, but I agree with the 

 late Mr. Conrad that his description indicates as do the types cited i 

 Nassse. 



P. ALTILIS, Conrad. PI. 3, fig. 28. Miocene, Virginin. 



P. SCALASPIRA, Conrad. PI. 3. iig. x)9. Miocene, Virginia. 



Subgenus PARANASSA, Conrad. Differs from Ptychosalpinx in the 

 submargin of the labrum being slightly thickened within and striate ; 

 siphonal canal shorter. Eocene, Miocene, America and Europi . 



P. GRANIFERA, Conr.* PI. 3, fig. 30. }'irr/ima. 



Subgenus TRITIARIA, Conrad. Elongated, subturrited, labrum not 

 thickened within. This does not seem to differ generically from the true 

 Xassas; it has very little resemblance to Ptycliomilpinx. 

 T. PERALTA, Conrad. PI. 3, fig. 31. Miocene, Virginia. 



[BuLLiOPSis, Conrad. Placed by its author at lirst as a subgenus of 

 Nassa, it was subsequently removed by him to Melanopsida^. It has 

 resemblance to 



(Joins NORTHIA, (Ji-iiy. 



The animal of tliis jrcnus is unknown, hut the opereulum has 

 been liji'iiri'd ly II. and A. Adams, in their "(JcmTa." The 

 shell is in its u'eueral nspeet much closer to J'un-ione.Ha in the 

 tainily Terebridse than to the ii'ener.-i with which it is lu-re (and 

 has been heretofore) associated ;, the variceal thickening at or 

 near the outer lip, is however, a feature which does not obtain in 

 Hie Terebridse. YW/om7/rt, inon-over, lias a coiicentrie o]>er- 

 eiiliini, with its nucleus near the middle of the inner inar^m. 

 Pel-Imps the figured operculuni of Xnrlhid is abnormal; 

 it has tliat ap|)earance. 1 think that if these slu-lls had not 

 been assimie<l to the ,\assid;r or 1<>:m\ ot lici" family, J would 

 have placed them in Tercbrid. ! prefer to allow tliem 



to remain here, rather than possibly complicate the subject b\- 

 their position. 



:; As one of the two specimens of the type of rdr-mu^ii is striate 

 within the aperture, while the other is smooth, probably the distinction 

 I'rom Plcltnudl'iiii.r will not hold 



