GASTEROPODA OF THE LOWER GREEN MARLS. 49 



tion. To this, in the present specimen, is added an unequal increase in 

 growth from an accident during life, and some slight compression from the 

 condition of its imbedding, the compression coming in a dorso-ventral 

 direction. I have given three figures of this specimen on PI. iv. Figs. 1-3, 

 for the purpose of correction. 



Mr. Meek^ has emended Mr. Conrad's generic description, as follows: 

 "Shell with body volution a little compressed dorso-ventrally; columella 

 flattened; spire about one-fifth the length of the aperture and canal;" citing 

 the same species as the type. Mr. Meek undoubtedly took his ideas of the 

 shell from Mr. Conrad's description and a very imperfect figure of the back 

 of the shell only. Of this I feel certain, for the reason that the tjrpe, which 

 is the property of the Am. Mus. Nat. Hist., New York City,, coming to them 

 tlu'ough Prof Holmes, of Charleston, South Carolina, was at that time 

 packed away in New York, and not opened until some years afterward by 

 myself Here he has increased the confusion by regarding the slight indi- 

 vidual imperfection and accidental compression as the principal and impor- 

 tant generic feature. Mr. Conrad^ adds still further to the confusion by 

 citing from the Paleontologia Indica, vol. 2, as belonging to this genus fig- 

 ures and species which are quite distinct from it. This also Mi-. Meek points 

 out. Mr. Meek^ in the earlier lines of his extended description of the genus, 

 states that the spire is " not papillate at the apex." The specimen is 

 slightly imperfect at the apex, but it shows plainly that it was papillate 

 at the apex when perfect, although but slightly so. Again, speaking of the 

 aperture, he says, "being angular, but not notched or canaliculate above," 

 which the specimen certainly is, and quite distinctly so. Still, notwith- 

 standing these features, Mr. Meek's genus Neptunella, with which he was 

 comparing it, is quite a distinct form. Mr. Conrad's genus may be char- 

 acterized as follows : 



Shell turbinate or pyriform; spire short; canal and beak short, slightly 

 bent in the lower part; columella smooth, thickened, slightly callous in 

 the upper part; aperture large, channeled above and narrowly contracted 



•Invert. Pal., vol. 9, U. S. Geol. Surv. Terr., pi). 343-344. j 



''Am. Jour. Conch., vol. 4, p. 248. 



3U. S. Geol. Surv. Terr., vol. 9, Invert Pal., p. 343. 



JMON XVIII 4 



