1890.] NATURAL SCIENCES OF PHILADELPHIA. 343 



TROCHID^ffil, NEW AND OLD. 

 BY H. A. PILSBRY. 



Since my monogruph of this family^ was written, a number of 

 specimens inviting notice have come into ray hands. 



Monodonta labio Linne, var. granulata Pilsbry. 



I have received from two sources specimens of a Monodonta refer- 

 able to labio, but having an interstitial row of granules in each inter- 

 liral groove ; these intervening grained lirai becom- 

 ing almost as prominent as the principal ones on 

 the last whorl. The number of granose lirre is thus 

 about doubled, giving quite a distinct aspect to 

 the shells. This is the more remarkable from the 

 fact that in the large suite of 31. labio before me 

 Fi^?T^ last year, none showed any trace of granose inter- 



stitial lirulre. The color is uniform ashen, one shell showing small 

 subsutural purple spots. All of the lira are markedly granose. 

 Monodonta neritoides Philippi. 



This shell I placed in the Section Neodiloma of the genus Mono- 

 donta, in the Manual of Conchology, although with considerable 

 doubt. From an examination of specimens recently presented to the 

 Academy by Mr. John Ford, it becomes obvious at once that both 

 M. neritoides Phil, and M. perplexa Pilsbry belong not to Neodi- 

 loma but to typical Monodonta; being furnished with a strong tooth 

 at the base of the columella. 



The description of Philippi applies to the specimen before me ex- 

 cept that this has a green streak outside the columella, and is larger ; 

 alt. 14, diam. 16 mm. The aperture is much more oblique than in 

 any other toothed species of Monodonta, except the M. perplexa, a 

 shell closely allied to neritoides, differing in color-pattern, the more 

 elevated acute spire, and the obvious spirals visible on the whorls 

 and within the mouth. 



Dunker's figures of neritoides (Index Moll. Mar. Jap. pi. 6, figs. 

 22, 23) are much more globose and smaller than Mr. Ford's example, 

 but agree well with numerous specimens before me collected by Mr. 

 Frederick Stearns in Japan. See also Manual of Conchology, xi, p. 

 468, pi. 38, figs. 20, 21. 



1 Manual of Conchology, 1st series, vol. XI, 18S9. 



