lANTHINID^E. 35 



M. Lucaze-Duthiers made interesting observations upon the 

 secretion of the float by lantliinse in captivity (Ann. Sci. Nat., 

 iv, 329, 1865 ; Ann. Mag. ]S T at. Hist., xvii, 278, 1866); Mr. Arthur 

 Adams has also given notes on the habits of these animals (Ann. 

 Mag. X. Hist., 3 ser., x, 417). Dr. Ruschenberger, in his Voyage 

 around the World, p. 21, remarks that when captured, the 

 lantlrina emits about a teaspoonful of violet liquid, and he 

 supposes that this copious discharge, like the ink of the cuttle- 

 fish, serves to facilitate the escape of the inollusk from its 

 enemies. 



Genus RECLUZIA, Petit, 1853. 



Shell paludiniform, thin, white under a brown epidermis ; whorls 

 ventricose ; aperture obliquely ovate, slightl} 1 " effused at the base, 

 peristome not continuous, the outer lip acute, entire, columella 

 oblique, somewhat sinuous. No operculum. 



Animal like lanthina, provided with a vesicular float. 

 - The species inhabit the Arabian Gulf and Pacific Ocean. 



Genus SCALITES, Conrad, 1842. 



Shell turriculated, whorls flattened above, carinated at the 

 shoulder, and convex below; outer lip sinuous; umbilicus none 

 or very small. S. ANGULATUS, Conr. Silurian. United States. 

 (Struct, and Syst. Conch., t. 67, f. 51.) 



The systematic position given this fossil as well as its sub- 

 genera, is mere guess-work. 



Subgenus RAPHISTOMA, Hall, 1847. 



Shell turbinated, more depressed, with carinated shoulder, and 

 convex below, as in the t} T pical group. S. STAMINEA, Hall 

 (Struct, and Syst. Conch., t. 67, f. 52). 



Subgenus HOLOPEA, Hall, 1847. 



This palaeozoic group is composed of incongruous elements ; 

 its first species has been referred to Littorinidse, another evi- 

 dently belongs to Naticidae, a third resembles lanthina. The 

 species are mostly casts, and there appears to be no good reason 

 for retaining the group. Gyclora, Hall, 1845, has been con- 

 sidered synonymous. 



