CHAPTER XI: THE MITRE SHELLS 



Family Mitrid/E 



Shell fusiform, solid, sometimes ovate-oblong; spire pointed, 

 never papillary; columella plaited, the smallest plaits nearest 

 the base; aperture narrow, often half as long as the shell; lip 

 thin, usually toothed; epidermis thin or wanting. Animal with 

 .small, narrow head, bearing tentacles with eyes and a cylindrical 

 extensile proboscis; mantle enclosed; foot small; radula variable, 

 the laterals in many broad and comb-like; siphon long, with 

 anterior appendage. 



Genus MITRA, Lam. 



A large genus between Voluta and Marginella. Species, 200, 

 in Tropics; the finest inhabit Australia and the Philippine Archi- 

 pelago. They are gregarious, nocturnal mollusks, avoiding the 

 light, hiding by day under rocks and coral masses along the reefs 

 Some burrow in sand. The heavy shelled species are sluggish. 

 All are most active at flood-tide. Ribbed species crawl about 

 coated with sandy mud, which is a protection from enemies. 

 Some species emit a purple fluid when disturbed. The shells 

 are among those most desired by collectors. 



American tropical species are among the large and gaily painted 

 forms. Those which dare the colder shores are smaller and less 

 ornate. Dr. Dall describes seventeen species on our southwest coast. 

 The Episcopal Mitre (M. episcopalis, d'Arg.) is fortunately 

 a shell widely distributed in tropical seas, else it would not be 

 within the reach and means of amateur collectors. As it is, 

 no one needs to go without it. Its tapering spire of smooth, 

 solid whorls is creamy white, overlaid with orange spots in regular 

 winding rows. The spots just below the sutures are large and 

 irregular. Those farther below are orderly close squares. The 

 large spots are darker than the others. The lip is toothed toward 

 its base. Length, 4 to 5 inches, Ceylon, PhilippineSo 



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