GASTEROPODA. 193 
columella, which is slightly oblique, narrow, and obtuse: interior 
vividly iridescent. 
There are two well-marked varieties, viz. : 
a. Thin, pearly, deep peach-blossom colour, the periphery deci- 
dedly angular, the fauces vividly iridescent, and the surface grooved 
with broad, shallow, transverse grooves. 
6. Solid, pale dingy yellow, surface smooth, whorls appressed at 
the suture, periphery less angular, and with vestiges of an epidermis. 
Axis five-eighths of an inch; diameter two-fifths of an inch. 
Obtained at Orange Harbour, Tierra del Fuego. (Couthouy.) 
This is perhaps the little Trochus spoken of by Quoy and Gaimard, 
as seen at the Falkland Islands. 
Figure 228, shell, with the animal as in crawling; 2284, plantar 
view of the animal; 2284, front view of the shell; 228c, the oper- 
culum. 
Marearita persica (Gould). 
Testa parva, solida, depressa, ovato-conica, levigata, nitida, intensé 
purpureo-incarnata: spira anfractibus quinque convexiusculis, su- 
perné dechvibus, ad suturam confluentibus: basis convexa, medio 
indentata, pallida ; columella lata, excavata, acuta, arcuata: apertura 
circularis ; faux vivide tridescens. 
SHELL small, solid, low ovate-conic, polished, of a peach-blossom 
colour: whorls five, convex, the largest declivous, with the periphery 
somewhat angular, at the suture closely appressed to the preceding 
whorl: beneath convex, the central region depressed and paler, not 
perforated. Aperture circular ; columella sharp, broad, and excavated, 
continuous with the lip, so as to form no angle with it at the base. 
Diameter half an inch; axis three-tenths of an inch. 
From among Cape Horn shells. 
49 
