DESCRIPTION. 163 



Shell rather smooth ; outer lip disengaged at the 

 base. 



Lister Conch, tab. 837. fig. 63. 



Specimen fuscous, thick ; lower whorl twice as 

 large as the next, the others longitudinally plaited 

 and transversely striate with three impressed lines. 



Inhabits the Indian Ocean. 



PLATE XVIII. 



Fig. 1. MuREX Trilulus, 



Shell ovate, with three rows of setaceous spines, 

 striate ; beak elongated, subulate, straight and 

 spined in the same manner as the body. 



Lister Conch, tab. 902. fig. 22. 



Specimen pale yellowish brown, with brown 

 spots on the transverse raised lines and striae ; aper- 

 ture white. 



Inhabits Asia, America, and the Red Sea. 



Fig. 2. M. ramosus. 



Shell with a triple row of foliations ; spire con- 

 tiguous ; beak truncate. 



m2 



