APPENDIX. 351 



general aspect ; volutions few, the last one much expanded ; 

 outer lip moderately' thin ; inner lip moderately thickened and 

 apparently without any callus ; the portion of the body, exclu- 

 sive of the last volution, very small and without a proper 

 columella. Family relations doubtful, but they are probably 

 with the Yelutinidse. [See p. 294, vol. ii.] 



TuRRiTELLA, Lam. [p. 224]. 

 SMiTHiA, Maltzan, 1883. Lilve Eglisia, but the whorls not in 

 contact, with revolving strise ; peristome simple. Operculum 

 corneous, multispiral. S. gracilis, Maltzan. Isl. Goree. 



Littorinidae [p. 240]. 

 Tphitus, JeflFreys, 1883. 



JEtym. — One of the Argonauts. 



Type. — I. tuheratu^, Jeffrej-s. Europe. 



Shell conical, covered with spiral rows of tubercles ; the apex 

 consists of a cylindrical process of several whorls, which is 

 closely striated lengthwise ; operculum horny, paucispiral with 

 a lateral nucleus. 



The peculiar apex may be compared to the styliform process 

 of lanthina and St34ifer,and there are several other genera, such 

 as Caecum and Turritella, in which the embryonic spire, which 

 had become useless for the occupancy of the mollusk, is decol- 

 lated or plugged up. 



RissoA, Frem. [p. 264]. 

 HEMiSTOMiA, Crossc. Mr. E. Marie, who collected this mollusk 

 in New Caledonia, writes to me that it is fluviatile ; it should 

 therefore be removed to the subfamily Hydrobiinas. 



DiPLOMMATiNA, Bcnson [p. 282]. 

 One species occurs in the island of Trinidad, West Indies. 



Helicinidse [p. 290]. 



The dentition (which is really rhipidoglossate) is erroneously 

 described from H. and A. Adams' " Genera." The figure referred 

 to, however, correctly represents it. The famil^y has been 

 usually included under the old order Scutibranchiata. 



Order SCUTIBRANCHIATA [p. 293]. 

 This order (and its suborders) may be suppressed. See p. 348. 



Velates, Montf. |^p. 298]. 

 VELATELLA (Meek, 1872), White, 1883. Shell resembling both 

 Dostia and Velates, suboval, flattened beneath, depressed-convex 



