MARGARITA. 283 



slightly angular; the next above is elevated, but the uppermost, and 

 frequently the two uppermost, are not elevated above the succeed- 

 incr whorl, so that the apex is obtuse ; everywhere covered 



® \ , -, ,. 1 • T i. 1 Fig. 544. 



with crowded and very hue revolvmg hues ; suture deep ; ^^^^ 

 aperture circular ; lip sharp, simple ; interior pearly and ^^ ^ 

 iridescent; umbilicus moderately large. Length, one m ar^-emaia. 

 tenth of an inch ; breadth, one eighth of an inch. 



Found in fishes caught off Cape Ann and Cohasset, in consider- 

 able numbers. Fishing Banks ( Willis) ; Grand Manan to Cape 

 Cod ( Stinipson). 



It is the smallest of the species of this genus that we find. It is 

 most obviously distinguished from small specimens of the last spe- 

 cies by its dead surface, which may w-ell be compared to chased 

 silver ; and, on a more intimate examination, it is f nmd to have 

 more uniform and decided revolving lines, and its spire is more 

 elevated. 



I was at first disposed to regard it as the 31. carnca, Lowe (Zool. 

 Journ. ii. 107, pi. 5, figs. 12, 13, 132). But, in the following essen- 

 tial characters belonging to that, it differs from our shell, viz., an 

 acutely pointed spire, an angular aperture, and a uniform yellowish 

 flesh-color. The revolving lines, too, are said to be elevated and 

 sub-distant, terms which allow of nmch latitude of meaning, Init 

 which we should not be likely to ap]>ly to the crowded, microscopic 

 lines on our shell. Tlioy appear (piite conspicuous on the figure 

 quoted. The young of M. undnlata would answer ])ctter to that 

 description. If it is not M. cantca, it has not been described ; Mr. 

 Sowerby hesitates to call it so. 



Margarita obscura. 



Fig. 171*. 



Shell depressed-conical, solid ; sj)ire obscure, reddish-brown, base ash-colored ; 

 whorls angulated by two or three revolving ridges ; lines of growth coarse ; aper- 

 ture circular, pearly within. 



Tiirlio ohscurns, Couthouy, Bost. Journ. Nat. Hist. ii. 100, pi. .3, fiff. 2. 



Maiyiirita obscura, Gould, Inv. 1st eil. 25,3, i\;j:. 171*. — Stimpson, Clicck Lists, 4. 



Shell small, solid, orbicular, low-conical, of a dull reddish-brown 

 above, and of a light ash color at base ; whorls five, convex, and 

 rendered angular alxmt the middle by a prominent revolving ridge ; 

 on the lower whorl are often one or two less conspicuous ridges, 



