280 TROCHID^. 



not larger than those on the base of our shell, while its base is 

 nearly f^mootll ; its umbilicus is much smaller. In color, size, and 

 general shape, the shells are alike. 



Margarita minutissima. 



Shell very minute, sub-ovately globose ; whorls three, convex, longitudinally 

 fiu'rowed ; spire short, obtuse; suture strongly impressed; aperture orbicular, 

 umbilicus large, deep. 



Margarita inimUisainvi , MiGHELS, Best. Jouni. iv. 349, pi. 16, fig. 5 (1S43). — Stimp- 

 SON, Check Lists, 4. 



Shell very minute, sub-discoidal, glolndar-ovatc, of a dull ash 

 color ; whorls three, convex, with distinct hnigitudinal, approximate 

 sulci, running obliquely, and disappearing as they ap- 

 proach the umbilical region ; spire very low and obtuse 

 at the apex ; suture deep, aperture circular ; lip sharp 

 and nearly continuous posteriorly ; vunbilicus large and 

 M.minutissima. pj.,jfQ^^i|(]_ Length, about one fifth of an inch; breadth, 

 about equal to the length. 

 Casco Bay. 



I have never found but a single specimen of this shell, which I 

 took from the stomach of a haddock. It is not very nearly allied 

 to any of the other species found on the coast. Under a magnifier, 

 it somewhat resembles M. varicosa, Nob., in the ultimate whorl. 

 It is, however, readily distinguished by its very depressed and oh- 

 tuse spire {Mig-hcls}. 



Margarita undulata. 



Fig. 172*. 



Shell orbicular, loAv-conical, dark flesh-color, encircled Avith regularly disposed 

 spiral lines, alternately larger and smaller, coarsely plaited at the sutures. 



Margarita undahita, Powerby, Malacol. and Conchol. Mag. i. 2fi ; Conchol Illust. {Mar- 

 fjnrita), fig. 4. — Gould, Inv. 1st ed. 254, fig. 172*. -De Kav, N. Y. Moll. 109. — 

 Stimpson, Check Lists, 4. 



Marrfarila striata, var. Gra;nlandica, Moi.i.ek, Ind. Moll. Gr. 



Tiirho incartiatiis, CotrTHOUY, Bost. Joiirn. Nat. Ilist. ii. 98, pi. 3, fig. 13. 



Trochus tumidus, Montagu, Lcth. Suev. pi. 30, fig. 3. 



Shell thin, orbicular, depressed-conical, usually of a bright brown- 

 ish-red color ; sometimes rose-red, at others pale flesh-colored ; whorls 

 four, convex, somewhat flattened above, undulated near the suture 

 by short folds or wrinkles, and encircled by numerous, elevated, 



