271 DR. P. P. CARPENTER ON NEW SPECIES 



rounded ribs, which are evanescent near the umbo. Inside with a 

 very few strong teeth, developed in a curved line. 



698. SCISSURELLA RIMULOIDES, n. Sp. 



S. t. rapide augente, albida, tenuissima ; apice celato ; anfr. 

 in., radiatim liratis, liris subdistantibus, acutis, obliquis ; um- 

 bilico magno; labro derlivi, haud Jisso, sed apertura postica, 

 ut in " Rimula" formata, subquadrata, elongata; liris trans- 

 versis gradus testa increscentis dejinientibus ; peritremate con- 

 tinuo, obliquo. 



Only one specimen was found of this beautiful little species, the 

 first known from America. It looks like a Velutina crossed by 

 sharp ribs in the direction of the slanting mouth. In the first whorl 

 *iie ribs are very close. It then assumes its normal sculpture, but 

 there is nearly a whorl before there is any trace of incision. This 

 appears to have begun as a slit, which was afterwards closed up. A 

 band, marked off by ten transverse ribs showing stages of growth, 

 encircles the shell as far as the hole, which is long find somewhat 

 octangular; but there is no band between the hole and fhe outer 

 iip. The shell furnishes a complete transition to Rimula. It is 

 preserved on tablet 2532. 



Long. -023, long. spir. '003, lat. '03 ; div. 140. 



Hab. Mazatlan ; off Spondylus calcifer ; Liverpool Collection. 



699. VlTRINELLA ORNATA, n. Sp. 



V. t. subdiscoidea, diaphana, tenuissima; anfr. iv., quorum iii. 

 primi nucleosi, insculpti ; ultimo carina maxima circa penphe- 

 riam ; postice subangulata, rugis radiantibus et striohs spi- 

 ralibus ornata ; antice carinata t carina nodosa ; basi carina 

 altera et ruais radiantibus ornata; umbilico angulato, satis 

 magno ; labro a carina indentato. 



Long. -015, lat. '028--035 ; div. (circ.) 175. 



Hab. Mazatlan ; one specimen off Spondylus, on tablet 2533 ; 

 Liverpool Collection. 



700. VlTRINELLA TENUISCULPTA, n. Sp. 



V. t. planata, diaphana, tenuissima; anf. iii. et dimidio, quorum 

 iii. nucleosi; striis elevatis, spiralibus y quorum una magna, 

 quasi carina prope suturam sculpta ; peripheria haud angu- 

 lata ; basi bis angulata, interdum rugis radiantibus distantibus 

 ornata; umbilico satis magno, carinato ; apertura undata,sub- 

 quadrata. 



The sculpture is not uniform over the last whorl. The principal 

 diagnostic features are the biangulated base, the infrasutural keel, 

 and the rounded periphery, 



Long. -016, long. spir. 0, lat. '023--03 ; div. 180. 

 Hab. Mazatlan; one specimen off Spondylus, on tablet 2534 1 

 Liverpool Collection. 



258 



