N A T I C A punctata, 

 Spotted Natica. 



Generic Character. —See PI. 75. 



Specific Character. 

 JV^. fesfd ovato-globosd, crassd, albd, strigis undatis puncfisque castanets 



ornatd ; tmihilico magna, aperto, mnplici ; columella: basiobsoletd. 

 Shell ovate-globose, thick, white with waved stripes and minute 



chesnut dots ; umbilicus large, open, simple ; base of the pillar 



obsolete. 

 Nerita pxmctata. Martini 11. pi. 197. /. 1903 and 4. Seba, pi. 38. 



/. 33 ? Gualt. pi 67./. M. and T. (good.) 

 Gochet. Adanson Sen. pi. 13. /'. 4. 



Ihe undulated brown lines in this shell, are sometimes 

 broken into three irregular bands of either lines or spots, be- 

 tween which are numerous minute dots ; in other varieties 

 these dots are only round the suture, and in some totally 

 wanting. Its most constant character rests on the umbilicus, 

 which is rather large, very deep, and without any appearance 

 of the base of the pillar. The mouth is also more con- 

 tracted than usual. It is said by Adanson to be common on 

 the coast of Seneoal ; and this observins; naturalist adds, that 

 the operculum is testaceous, of a pure white, and marked 

 with numerous concentric grooves at the upper angle. 



NATICA efFusa. 



JV^. testa depressd, albd, maculis castaneis ornatd ; spird brevisaimd ; 



columella: basi crassd, pland, ad labium interius sinu annexd- 

 Shell depressed, white, with chesnut spots ; spire very small ; 



umbilicus large, open, spreading; base of the pillar thick, 



flat, and united to the inner lip by a sinus. 



In form, and sometimes in colour, this shell bears a close 

 resemblance to the oval variety of N. mamilla (Nerita via- 

 milla Lin.); but, the umbilicus, instead of being entirely 

 closed up, is remarkably open, very deep, and the pillar 

 forming an elevated ridge within ; colour in the shells of 

 this genus is a very secondary, and, in many cases, a most 

 fallacious guide for the discrimination of the species ; for 

 this is sometimes pure white, and I have specimens o^ N.ma- 

 tiiilla entirely orange. This is a rare shell, probably from 

 India. 



PI. 104. 



