Lamarck's Genera of Shells. S3 



is not contiguous to the body of the shell, as in the rostellaria, but 

 at a distance from it, as in the strombi, which differ from the pte- 

 rocera, only in wanting the digitations of the dilated wing, and by 

 their short canal. 

 The pterocera are generally large shells. 

 Type. Pterocera lambis*. (Strombus lambis. Linn.) 

 Shell oblong oval, tubercular-gibbous, heptadactylous, variegated 

 with red and brown ; terminal digitations straight ; spire acute 

 conical ; aperture very smooth, rosy. Indian Seas. PI, v. Fig. 185, 

 7 Species. 



3. Strombus t. 



Shell ventricose, terminated at the base by a short, notched, or 

 truncated canal. Right lip dilated by age into a simple wing, 

 lobed or crenate at the upper part ; on the lower part a sinus dis- 

 tinct from the canal or notch of the base. 



Distinguished from pterocera by the dilated right lip not being 

 divided by longitudinal digitations, as is the case with that shell, 

 and by the canal at the base being very short, truncated, or notched : 

 from rostellaria by the sinus being separated from the canal by a 

 portion of the lip, whereas in the former it is contiguous to the canal. 



Some strombi are of moderate size, even small, but some are 

 very large and thick shells. 



Type. Strombus latissimusl. (Idem. Linn.) 

 Shell turbinated, ventricose, smooth on the back, with the wing 

 subrugose; orange, spotted with white ; spire short, nodular; lip 

 very broad, rounded above, projecting beyond the spire, margin 

 acute, side very thick; aperture smooth, white, with a rosy 

 tint. Indian Ocean. PI. v. Fig. 186. 32 Recent species, and 

 1 fossil. 



• The term used by the old French conchologists for those strombi, which 

 have large, projecting tubercles, and stria; on the external surface, and the 

 aperture very smooth, and flesh-coloured. Thus, strombus gigas, was a lampis. 

 Diet. D'UUtoire Nalurelle. Lamarck's second species — bis type is P. truncuta, 



t Original Latin name for a sort of shell fish, fYom the Greek iflpitlStf. 



% Very brond. Lamarck's third spetics~his typo is S. gigai. 



