192 INVERTEBRATA OF MASSACHUSETTS. 



Hp. It is almost precisely like the Turbo cary'chium of Montagu ; 

 {Caryichium minimum of Leach.) It is much smaller than P. corlicd- 

 ria, and its aperture differs in having the tooth of the transverse lip 

 near the inner, instead of near the outer termination. 



Pupa fallax. 



Shell turretied, dusky ; whorls six, smooth, convex ; suture dis' 

 tinct ; aperture sub-oval; lip widely reflected; umbilicus distinct. 



Figure 123. 



State Coll., No. 63. Soc. Cab., No. 1139. 



Cyclostoma marginata, Sav ; Juurn. Jcad. JVat. Sc, ii. 172. 

 Pupa fallax? Say ; Jour Acad. JVat. Sc, v. 121 



Shell small, turretted, regularly and not rapidly tapering to a 

 somewhat pointed apex ; color dusky or light horn-color ; 

 whorls six, shining, moderately convex, very slightly and finely 

 wrinkled ; suture well impressed ; aperture less than one third the 

 length of the shell, rounded oval, somewhat irregular; the preced- 

 ing whorl forms a nearly transverse boundary above, and is usually 

 enamelled ; the pillar lip is nearly straight, and turns abruptly at 

 the front, so as to form nearly a right angle ; front broadly 

 curved ; outer lip white, widely and equally reflected and thick- 

 ened ; umbilicus distinct. Length ;i inch, breadth y'-y inch. 



I have seen but two or three specimens of this shell which 

 have been found in Massachusetts, one of which was sent me by 

 Dr. L. M. Yale, from Martha's Vineyard ; I have seen others 

 from Rhode Island. It is found abundantly in Ohio. 



This shell is certainly not a Cyclo'stoma, for its aperture is not cir- 

 cular, nor has it an operculum of any kind. It belongs to Pupa 

 rather than to any other existing genus, except, perhaps, the genus 

 Pa'rtula. If it is brought under this genus, the specific name must 

 be changed, as Mr. Say suggests. He described a shell from Massa- 

 chusetts under the name of Pupa fallax, which he says very much re- 

 sembled his Cyclostoma marginata, except that it was much larger. 

 He seems to have re-described the same shell, in the " New Harmony 

 Disseminator," under the name of Pupa pldcida. It may not be im- 

 proper, therefore, to apply the first of the above names to the shell 

 under consideration, while the latter is retained for the larger shell, 



