THE NAUTILUS. 135 



marks of tlie sculpture of the shell, and of the dilation of part of the 

 labrum on the. right side of the base of the aperture, allies this species 

 with Gldiidinn leucozonias and dominicensis, botli of which occur in 

 the Parish of Portland in the extreme eastern part of the island. 



POLYGYKA STEN01REMA WITHOUT A LIP-NOTCH. 



1JV IIIOXKY A. PILSBHV. 



Mr. Bryant Walker has sent me for examination a specimen agree- 

 ing with Polyyyra stenotrema in the main, except that the basal lip 

 is without the usual median nick or notch. The parietal lamella is 

 strong and high, as usual in the species. Form rather elevated. 

 Alt. slightly over 6, diam. <s.7 mm. It was taken by Mr. Walker at 

 Dalton, Georgia ; being the only stenotrema collected at that place. 



In the collection of Mr. Geo. H. Clapp are two specimens, formerly 

 in the James Lewis collection, labeled " East Tennessee," which 

 agree with Mr. AValker's Georgia shell in lacking the lip-notch, 

 although in one a slight wide sinuation of the lip in place of it, is 

 perceptible. They measure 8 and 8.5 mm. diam., one with high, the 

 other moderately low spire. All of the specimens show hairs or their 

 traces, as in P. stenotrema, though not very conspicuously. 



The lip-notch in the stenotrema species corresponds of course to 

 the space between the lip-teeth in Triodopsis, the thickened ledges on 

 each side of the notch being homologous with the basal and outer 

 teeth in such species as P. tridentata. These notchless shells there- 

 fore represent cases of confluence or concrescence of teeth, a some- 

 what rare occurrence in Helices. 



The question arises, are these shells merely abnormal forms pro- 

 duced by some mantle injury or other abnormal condition, or do they 

 represent a rare race of which the notchless lip is characteristic? 

 The former alternative seems most probable, except that the shell 

 and lip seem quite without trace of any evidence of a diseased con- 

 dition of the mantle, which is usually manifested by some roughness 

 in the deposition of lime at the lip, or irregularity in the cuticle be- 

 hind it. 



However, the question is not one to be decided off-hand, but by 

 the examination of more material ; and I would ask collectors to go 

 over their specimens of P. stenotrema and allied species, and report 



