184 POPULAE BllITISH CONCHOLOGY. 



We are among the Canalifera now ; for all ilie spiral 

 shells of M7iricid<2 have a more or less produced groove at 

 the end of their apertures, through which passes a siphon, 

 formed of a lengthened and rolled-up portion of the mantle. 



The MtiricidcE are the very eagles, tigers, and constric- 

 tors of their class, feeding on living victims, and taking so 

 large a meal at one time as to require a period of rest for 

 digestion. Each small victim, or portion of a larger one, 

 ere it passes into the body of its ferocious devourer, has to 

 run the gauntlet tlirough a long proboscis, lined by a 

 tongue, armed with triple rows of teeth. The following are 

 British representatives of this family : — 



I. MuREX. — The latest monograph of this genus is that 

 by Mr. Eeeve, in his ^Conchologia Iconica,^ in which nearly 

 two hundred species are described, and pictorially represen- 

 ted, — a task of no small difficulty ; for nearly all the species 

 have, running up the spire, from whorl to whorl obliquely, 

 a varix, or swelling, marking the edge of former apertures ; 

 and these varices are often armed with branches, spires, 

 fringes, teeth, and furbelows of the most complicated de- 

 scription. 



If we had to choose a characteristic example of the genus 

 as to the shell, we certainly should not fix upon either of 



