NATICA. 



Plate XXX. 



Speries U2. (Fig-. U2, 144, 145, and 14G, 

 Mus. Cumiug.) 

 Natic.^ Helicoides. Nat. testa vix rimuto-umh'diciitd, 

 ovatd, Ampullariaformi, spird exsertd, siiturd cov- 

 splcue canaliculatd, anfractiius convexis, basin versus 

 xuhnttenuatim productis, aperturd ovatd, Itasi effiisd, 

 rrtliimeUd teuuite!' marginatd ; calcareo-nlhd , npider- 

 atidf Iciiiii cormd decidud indtdd. 

 The Helix-like Natica. Shell slightly edge-umbili- 

 cated, ovate, AmpuUaria-like, spire exserted, suture 

 conspicuously channelled, whorls convex, somewhat 

 attenuately produced towards the l)ase, aperture 

 ovate, effused at the base, columella thinly edged ; 

 challc-white, covered with a thin yellowish horny 

 deciduous epidermis. 

 .loHNSTON, Trans. Nat. Hist. Soc. of Berwick-on-Tweed, 

 for 1835. 



Natka canalicidata, Gould. 

 Natica Islandica ? Gmelin. 

 Hnh. North Seas. 



The accompanying figures, 142, 144, 145, and 146, se- 

 lected to represent N. Helicoides, caualiculata, and Is- 

 Inndicn, as so many distinct species, are without doubt 



one and the same. It has much the appearance of an 

 Ampiillaria or Paludina, but may be readily distinguished 

 by its more calcareous marine aspect and deciduous epi- 

 dermis. 



Species 143. (Mus. Cuming.) 

 Natica cornea. Nat. testa mimite rimato-uyiljiliratd, 

 ovatd, teiini, subinjlatd, spird exsertd, suturd canalicu- 

 latd, anfractibus convexis, ad basin rotundato-produc- 

 tis, aperturd ovatd, columelld tenniter marginatd; 

 calcareo-nlM, epidermide corned fused decidud indutd. 

 The horny Natica. Shell minutely edge-umbilicated, 

 ovate, thin, rather inflated, spire exserted, suture 

 channelled, whorls convex, rotundately produced at 

 the base, aperture ovate, columella thinly edged ; 

 chalk-white, covered with a brown homy deciduous 

 epidermis. 

 MoLLER, Ind. Moll. Groenlandiae, p. 7- 

 Hah. Greenland. 



Loven quotes this as a synonyme of the preceding spe- 

 cies, but it is of a more broadly inflated form, and charac- 

 terized by a darker epidermis. 



