1902.] 



NATURAL SCIENCES OP PHILADELPHIA. 



421 



Oastrodonta interna 



andrewsoB 



multidentata 



lamellidens 



clappi 



walkeri 



significana f 



capsella 



capsella placentula . 

 AgrioUmax campestris. . 

 Philomycus carolinensis. 



tcetherbyi 



hemphUli 



R F 8 



XXX 



X X 



X 



XXX 

 X 

 X 



x' 



X X 



X X 



X 



XXX 



X 



XXX 



Pyramidula alternata 



alternata fergusoni ? . . 

 alternata costata .... . 



alternata mordax 



perspectiva , 



hryanti 



Helicodiscus lineatus , 



Punctum pygmcEum 



blandianum 



Sphyradmm edentulum 



Succinea ovalis 



CarycMum exigunm 



List of Species. 



HELIOINID^. 

 Helicina occulta Say. 



Wilson's Cove, Mt. Mitchell. A few large specimens, diam. 7;^ to 

 8 mm., were found under the dead leaves around the roots of the 

 basswoods and buckeyes ; all were of the uniform deep reddish-yellow 

 color characteristic of the species from other localities. There was 

 no apparent tendency to the great variation in color noted by Weth- 

 erby in the Roan mountain specimens. 



HELIOIDJB. 

 Polygyra tridentata (Say). 



With the exception of the large variety found at Paint Rock 

 mentioned below, this species, which was found nearly everywhere, 

 shows but slight variation fi'om a common type, which seems 

 decidedly characteristic of the whole region from Roan to the 

 Smoky mountains. It is usually rather small, varyhig froni 12i 

 to 14 ram. in diameter at Roan to 17 to 18^ at Bluff mountain. 



The size seems to increase quite regularly from the north to the 

 south, specimens from Cat-tail (14 to 15) being smaller than 

 those from Wilson's Cove (13| to loj), while these are decidedly 

 smaller than those from Paint Rock and Bluff mountain. This 

 race, for it hardly seems to be suflScieutly differentiated to be entitled 



^Specimens from Roan before us beloug to the smooth form herein- 

 after meationed, but are not typical fergusoni. Wetherby's specimena 

 were probably the same. 



