MARINE MOLLUSCA OF THE UNITED STATES. 103 



pressed, imperforate ; surface reticulated by fine microscopic 

 striae; lip arising from the margin of the circular pit at the sum- 

 mit of the spire ; aperture linear above, broad below ; umbilicus 

 covered with enamel, which gradually disappears within the aper- 

 ture ; white under a ferruginous epidermis. 



Length 7.5, diam. 2.5 mill. 



New England, northwards. {Eur.) 



2. C. ORYZA, Totten. Fig. 209. 



{Bulla.) Am. Jouru. Sci., xxviii. 350, t. 5. 1835. 



Shell minute, not very thin ; tip depi'essed into a shallow pit, 

 and base rather acute ; aperture as long as the shell, narrow above 

 and wider below ; outer lip sharp, regularly arched rising a little 

 higher than the shoulder ; an oblique, truncated fold on the colu- 

 mella ; white. 



Length 7.5, diam. 2.5 mill. 



Neio England, south of Cape Cod. {Eur.) 



According to Mr. Jeffreys this shell = B. utricuhis, Brocchi, 

 18U. 



Genus UTRICULUS, Brown. 

 Brit. Conch. 1844. 



Head disk very short ; tentacular lobes lateral, rounded ; eyes 

 none. 



1. r. GouLDii, Couthouy. Fig. 210, 211. 



{Btilla.) Bost. Journ. Nat. Hist., ii. 181, t. 4, f. 8. 1839. 

 U. turritus, Moller, lad. Moll. Grcenl. 1842. 

 Bulla pertenuis, Mighels, Proc. Bost. Soc, i. 129. 1843. 



Shell thin, small, of four whorls, rounded at their upper edges, 

 with well-defined sutures and line transverse strige; spire de- 

 pressed, discoidal, sometimes slightly mammillated; no umbilicus ; 

 white, with yellowish epidermis. 



Length 7.5, diam. 2.5 mill. 



New England. {Eur.) 

 The Bulla pertenuis of Mighels (Fig. 211) appears to be the 

 young of Gouldii. 



2. U. CANALicuLATUS, Say. Fig. 212. 



{Volvaria.) Journ. Philad. Acad., v. 211. 1826. 

 Bulla obsiricta, Gould, Am. Journ. Set., xxxviii. 196. 1840. 



Shell minute, cylindrical, polished, with very faint lines of 

 growth ; spire convex, a little elevated, with minute but promi- 

 nent tip ; whorls about five, with their shoulders very obtuselj' 



