8 



rather elevnted and obtuse at l)ot1i extremities ; cancel- 

 lately ribbed; a few of the ril)s pale pnrple; dorsal aperture 

 small, much nearer to the anterior than to the posterior 

 end, its margin internally truncated posteriorly : mar- 

 gin crenated. 



Obs. The only two specimens I have seen were in 

 G. Humphrey's collection, they are now in Mr. Cuming's. 



GG Fissurellarugosa, mi/ii. Conch. Illust. f. 54. Shell of a 



rather lengthened oval shape, depressed, whitish, varied 

 with dark redbrowii,and covered with a few large rugose 

 radiating ribs and some smaller interstitial ones ; dorsal 

 aperture nearer to the anterior extremity, oblong,its in- 

 ternal margin rather wide, with a dark border ; inside 

 green ; edge of the whole shell irregularly sinuous ; length 

 1*0 breadth OG inches. Gallapagos Islands,Mr. Cuming. 



G7 Mexicana mlhi, Conch, Illust. f. 61. Shell oblong, 



reddish brown, with darker rays, and numerous close-set 

 radiating grooves which are decussated by very fine con- 

 centric strise ; dorsal aperture oblong, rather contracted 

 in the middle, and with two obsolete teeth on each side ; 

 inside white, with a purplish brown crenulated margin ; 

 length 125, breadth O'oG. Eeal Llejos, Mexico; Mr. 

 Cuming. 



(*,8 crenifera, }m/ii, Zool. Proc. p. S . Conch. Illust. 



f. 73, Eeal Llejos, Mr, Cuming. 



