246 MAZATLAN rTNIVALTES 



309. VlTEINELLA CAEINULATA, n. S. 



Y. t. suhglohosCi, suhdeprcssd, tenui, suhdiaphana ; suiurd im- 

 pressd ; umbilico hmid magno ; regione umhiUcali magna, 

 concavd, ra.iiatim rugosd ; avfr. tilt, carinulis v. haud promin- 

 entibus, quarum dues infra et siLpra peripheriam hmid planatam 

 Slice, sunt, diire in spird liaud planatd, altera regioncm umbili' 

 calem describens ; sulcis splraUbua in basim, carinulis simu- 

 lantibus ; aperturd subelongatd, ad basim angulatd, anfr. penult. 

 pa rum atiingente. 



Known from V. cincta by the non-prominence of tlie keels, 

 rounding and keeling of the spire, and greater elevation. The 

 only specimen found is not matvire, scarcely a whirl being 

 formed of the adult portion. Long. '22, lot. "03 by '023, 

 div. circ. '165°. 



JIab. — Miizatlan ; 1 sp. oiF. Spondylus ; L'pool Col. 



Tablet 1 160 contains the specimen. 



310. PVlTRINElLA NATICOIDES, n. S. 



? V. t. subghhosd, gubdepressd, nitidd, subdiaphand, albd ; 

 anfractibus iv. et triente, quarum primi convexiusculi sunt, 

 uUimi sutura vix impressd ; striulis incrementi exilUmis, max- 

 inie stiturani versus, haud conspiculs ; umbilico profunda, an- 

 gusto, a carina exiante callosd d^initd ; aperturd anfr. penult, 

 parum attlngenie, labia subexpanso, a earind angulato. 



This curious shell might bo either called by the above name 

 or Natica vitriuelloides, as it partakes of the characters of 

 both genera ; though the texture and difference of convexity 

 in the first three whirls incline the balance in favour of the 

 former genus. Thus the shell alone cannot decide between 

 animals widely removed. It looks like a flattened, white, 

 glossy Natica, witli the straight umbilicus bounded by a con- 

 spicuous keel which runs into the aperture. Long. "03, lat. .047 

 by -04, div. IGO". 

 jffai.— Mazatlaii ; 2 sp. off Spondylus & Chama ; Lpool Col. 



Tablet 1161 contains the largest specimen. 



311. PVlTRINELLA PLANOSPIEATA, n. S. 



?V. t. magnd (quoad germs), tenuissimd, subdiaphand, albd; 

 spird planatd, ad carinas valde angulatd, spiraliter striatd; 

 ad basim tumcnte, convexd, prqfunde sed noii late wnbilicatd,' 



