246 MAZATLAN UNIVALVES 
309. VITRINELLA CARINULATA, 7. s. 
V. é. subglobost, subdepressd, tenui, subdiaphand ; suturdé im- 
pressi ; umbilico haud magno ; regione wmnbilicali magna, 
concavd, radiatim rugost ; anfr. ult. carinulis v. haud promin- 
entibus, quarum due infra et supra peripheriam haud planatam 
sue sunt, due in spird haud planatd, altera regionem umbili- 
calem describens ; sulcis spiralibus in basim, carinulis simu- 
lantibus ; apertura subelongatd, ad basim angulaté, anfr. penult. 
parum attingente. 
Known from V. cincta by the non-prominence of the keels, 
rounding and keeling of the spire, and greater elevation. The 
only specimen found is not mature, scarcely a whirl being 
formed of the adult portion. Long. *22, lat. ‘03 by °023. 
div. circ. °165°. 
Hahbh.—Mazatlan ; 1 sp. off. Spondylus; L’pool Col. 
Tablet 1160 contains the specimen. 
310. P VITRINELLA NATICOIDES, 7. s. 
2?V. t. subglobosd, subdepressd, nitidd, subdiaphand, albé ; 
anfractibus 1. et triente, quarum primi convexiusculi sunt, 
ultime suturd vie impressé ; striulis incrementt exillimis, max- 
ime suturam versus, haud conspicuis ; umbilico profundo, an- 
gusto, & carina extante callosd definitd ; aperturé anfr. penult. 
parum attingente, labio subexpanso, a caring angulato. 
This curious shell might be either called by the above name 
or Natica vitrinelloides, 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, with the straight umbilicus bounded by a con- 
spicuous keel which runs into the aperture. Long. ‘03, lat. .O47 
by °04, div. 160°. 
Hab.—Mazatlan ; 2 sp. off Spondylus & Chama ; L’pool Col. 
Tablet 1161 contains the largest specimen. 
311. PViTRINELLA PLANOSPIRATA, 2. S. 
2V.t. magna (quoad genus), tenuissind, subdiaphand, alba ; 
spirad planatd, ad carinas valde angulatd, spiraliter striaté : 
ad basim tumente, convexd, nrofunde sed non late umbiliecaté ; 
