UTRICULUS. 217 



enamel upon the body of the shell, partially coverino- an umbilical 

 indentation placed at about one fourth the length of the shell. 

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



Obtained from fishes taken in Massachusetts Bay. Connecticut 

 {Linslei/} ; Grand Manan {Stimpson) ; Maine (^Mig-Iiels) ; Green- 

 land (iJfdrc/O- 



This shell has no marked resemblance to any other with which I 

 am acquainted, unless it be to B. Gouldii, of which it may possibly 

 be the young. It is, however, much smaller and thinner, more 

 globular, and its greatest breadth is before, instead of behind, the 

 middle. The peculiarity of the base, also, is well marked. In many 

 respects it has a general resemblance to Montagu's B. diapliana 

 {Test. Brit. pi. 7, fig. 8), but that has an elevated spire, and is not 

 umbilicated. Brown figures a shell, which he calls Diapliana pel- 

 lucida (^ConrJi. of Great Brit. &c., pi. 38, figs. 10, 11), which bears 

 a still more striking resemblance. 



These two last-named species would come under the sub-genus 

 Aplustra of Blainville ; in which the whorls are all visible, but the 

 spire not projecting ; and in which there is a thickened portion at 

 the anterior termination of the pillar. 



Oeuus UTRICULUS, Brown. 1844. 



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

 none. 



Shell rather thin, sub-cylindrical, imperforate, covered with an 

 epidermis ; spire distinct ; apex obtuse, not mammillated, sutures 

 simple, not canaliculated ; aperture narrow behind, dilated and 

 entire in front, nearly as long as the body whorl ; columella sim- 

 ple, not plicate ; outer lip straight, acute. 



Utriculus Gouldii. 



Fig. 94. 



Shell ovate, white, rather opaque, composed of four whorls, the last including 

 all the others, and covered with minute revolving lines ; spire nearly flat. 



Bulla Gouldii, CocTHOUY, Bost. Journ. Nat. Hist. ii. 181, pi. 4, fig. 6 (1839). — Gould, 



Inv. 16.3, fig. 94. -De Kay, N. Y. Moll. 15, pi. 5, fig. 101. 

 Utriculus Gouldii, Stimpson, Check Lists, 4 (1860). 



Shell small, ovate, shining, of a dead white color, covered with a 

 yellowish epidermis ; whorls four, rounded at their upper edges, 



