PHYLLOBRANCHIA. TURBONIDZ. 177 
it has likewise been found amongst shell-sand from Padstow in 
the same county by my worthy friend Dr. Goodall, the Provost 
of Eton. It was first discovered by Mr. J. Cranch in deep 
water off Falmouth Harbour. 
4. GIBBULA MAGUS. 
G. testa anfractibus elevato-lineatis. Sutura profunda. 
Trochus magus, Lister, Conch. t. eececexli. f. 32; Gualt. Test. 
t. xiv. f. ce. ; D’ Argenv. Conch. t. vii. f. 5.; Seba Mus. iii. 
t. xli. f.4, 6; Knorr. Vergn. vi. t. xxvil.f. 4; Penn. Brit. 
Zool. 1. 127. t. Ixxx. f. 107; Chem. Conch. v. t. clxx. 
f. 1656-1659: Pult. Cat. Dorset. 44. t. xvi. f. 1; Donov. 
Brit. Shells, t. viii. f. 1; Mont. Test. Brit. 283; M.& R. 
Trans. Linn. Soc. vill. 151: Flem. Edinb. Encycl. vii. 75 ; 
Dill. Desc. Cat. 186. 
Habitat in littoribus maris Europzi vulgatissima. Alt. 13 
unc. | 
Shell with its whorls with elevated lines; its suture deep. 
Height one inch and a half. 
Inhabits the shores of the European seas very commonly. 
Genus 78. NaTICA. 
Natica Lamarck. 
Nerita Auctorum. 
Testa subglobosa, umbilicata. Umbilicus obliqué locatus, 
profundus. Apertura integra, semirotunda. Peritrema pos- 
tice tenuissimum, super umbilicum callosum, umbilicum coare- 
tans, interdim obtegens. Operculumcorneum. Animal ore cy- 
lindrico, emarginato. Tentaculis duobus, elongatis, acuminatis, 
ad basin externé oculigeris. (Oculis sessilibus, rotundis.) Pa/- 
lio valdé dilatato, testam feré totam tegente, et pede lato, testa 
breviore instructo. 
The shell subglobose, umbilicated ; its umbilicus deep and 
sinuated obliquely ; its aperture entire, half-rounded ; its peri- 
treme very thin behind, but hard above the umbilicus, which 
it contracts and sometimes covers entirely; its operculum horny. 
Eo 
