37S STROMBIDJE. CERITHIID.E. 



Murex. In their habits the Muricidoa resemble the Buccinidae, 

 preying upon other Mollusca, through whose shells they bore by 

 the agency of their rasping tongue. 



992. The last family of the siphonated Gasteropods is that of 

 the STROMBID^E, or Wing-shells, in which the outer lip of the 

 shell is widely expanded, and deeply notched in the vicinity of 

 the siphonal canal. The animal has a small narrow foot, which 

 is not well adapted for the ordinary creeping motion of the Gastero- 

 pods ; but the Strombidse are nevertheless very active, progress- 

 ing by a series of leaping movements. The foot is furnished 

 with a peculiar process, which bears an elongated operculum, 

 serrated on one side ; the proboscis is very large, annulated, and 

 capable of being protruded to a great distance ; and the eyes are 

 very large and perfect, and supported at the extremity of thick 

 footstalks, from the middle of which the short tentacles take 

 their rise. These curiously organised creatures are most abund- 

 ant in the seas of warm climates, where they feed principally on 

 decomposing animal matter. Many of them are of large size and 

 remarkable forms, the surface and margin of the shell being 

 often adorned with spines or large tubercles, as is the case in the 

 Pteroceras already referred to (Fig. 657). The Strombus gigas 

 of the West Indies, a well-known species, is on^e of the largest 

 Mollusca ; its shell often measures a foot in length ; and the 

 apex and spines being filled up with solid shell, as the animal in- 

 creases in age, an old shell usually weighs several pounds. The 

 shelly matter of the interior, which exhibits beautiful pink tints, 

 is much used in the manufacture of cameos ; and immense numbers 

 of the shells are imported into this country for that purpose. 



993. Of the non-siphonated Pectinibranchiate Gasteropods, 

 the majority of which are vegetable feeders, the nearest approach 

 to the preceding families is made by the CERITHIIDJE, in which 

 the anterior margin of the aperture of the shell exhibits more or 

 less distinct traces of a canal, and the margin of the mantle pos- 

 sesses a siphonal fold at the corresponding part. The outer 

 margin of the aperture is usually widely expanded. These cha- 

 racters, which especially indicate a resemblance to the Strombidae, 

 are presented with the greatest distinctness by the well-known 



