48 MigheW and Adams^ Descriptions of 



Habitat. Casco Bay ; taken from stomachs of haddock, in 

 the summer of 1840, and subsequently. 



Remarks. This is the only species of true Trochus that 

 has ever been discovered on this Atlantic coast. It is not 

 nearly allied to any species with which we are acquainted, 

 unless we regard Turbo (Margarita) dnereus, Couth. — Tro- 

 chus costalis, Loven, as a true Trochus. A careless observer 

 would be likely to confound them ; but besides several other 

 essential points of difference, our shell is easily distinguished 

 from all the known species of Margarita, by the absence of 

 an umbilicus. 



CINGULA LATIOR. 



Plate IV. Fig. 22. 



C. testa minima, ovato-conica, laevi, pallida; anfractibus quatuor, convexis ; 

 sutura impressa ; spir^ quam apertura longiore ; anfractu postremo magno ; ap- 

 ertura sub-ovata 3 operculo corneo. 



Shell minute, ovate-conic, smooth, pale horn -color ; whorls 

 more than four, convex ; suture much impressed ; spire three- 

 fifths of the length of the shell ; last whorl broad, larger than 

 the rest of the shell ; aperture ovate-orbicular, left margin 

 with a lamina ; operculum horny. 



Length ,08 inch ; breadth ,05 inch ; divergence 60 degrees. 



Habitat. Casco Bay ; taken from the stomach of a haddock 

 in the spring of 1841. 



It is in the cabinet of J. W. Mighels. 



Remarks. This species has a slight resemblance to O. 

 minuta, Totten, in the absence of sculpture ; but the spire is 

 shorter, more pointed, and its divergence is much greater, 

 giving a very different form to the shell. It is, moreover, a 

 much smaller shell. It appears also to be allied to Turbo 

 reticulatus, Montagu, but is distinct from that species in not 

 having as many turns by one and a half ; it differs, also, in 

 not being " strongly striate, both longitudinally and trans- 

 versely," and in not having the '' aperture thickened by a rib." 

 It has been found very rarely, usually in company with O. 

 semicostatus and C. arenajius, Mont. 



