Lamarck's Genera of Shells. 51 



colour; belly large, bifariately spinous; spines straight, chan-, 

 nelled ; spire rather prominent, muricate; beak naked towards its 

 extremity. Mediterranean and Adriatic. PI. v. Fig. 182. GG Re- 

 cent species, and two fossil. 



11. Triton*. 



Shell oval or oblong, channelled at the base ; varices alternate, 

 or rare, or nearly solitary, on the separate whorls, and never ar- 

 ranged in longitudinal rows. An operculum. 



Sometimes the triton has only one varix, viz., that on the right 

 lip, which is never wanting. The varices are generally smooth ; 

 never spinous. 



Type. Triton variegatum^. (Murex Tritonis. Linn.) 



Shell elongated-conical, trumpet-shaped, ventricose at the lower 

 part, surrounded with very obtuse, smooth ribs ; elegantly vari- 

 egated, with white and red; edges of the sutures wrinkled; 

 aperture red ; columella with white wrinkles ; and one plait on the 

 upper part ; margin of the lip spotted with black ; spots terminated 

 by two short white lines. Asiatic Seas. PI. v. Fig. 183. 

 31 Species. 



2d Family. 

 Alata. (3 Genera.) 



A canal, of variable length, at the base of the aperture, the 

 right lip of which changes its form by age, and has a sinus at the 

 lower part. 



A remarkable circumstance prevails in the shells of this family 

 which is scarcely found in any others, except the cypnea, namely, 

 the difference of form which exists between the young shell and the 

 adult, so that the former has often very little resemblance to the 

 latter. 



Linneus considered all the alata as strombi, in which genus he 

 has included shells that by no means belong to it. The essential 



* A sea deity, the son of Neptune and Aniphitrite. 



t Variegated. Wliy our author lias chosen to make this name neuter, we are 

 at a loss to guess. 



E2 



