3U2 A MAXUAu OF AxMERICAN LAND SHELLS. 



lias an obsolete, toolli-like developnieiit near tbe coliiniella. The aper- 

 ture is more lunate tlian in jejunus. 



]\[. Moinlianns may be compared, so far as regards tlie tuu)id base, 

 small und)ilicus, constricted aperture, and gibbous character of tbe su- 

 perior i)art of the last wborl bebind tbe aperture, with a Texas form in 

 my cabinet of Dorcasia BerJandieriana. 



Tbe measurements of my largest specimen (G wborls) of 31. Mobilianus, 

 from Baldwin, are as follows : Greater diameter 10, lesser 7"'™ j beigbt, 



fjniin 



Jaw of Mobilianus as usual ; 10 ribs. 



Liugmil membrane of tbe true Mohiliauus from Baldwin County. Ala- 

 bama, bas 25-1-2^ teetb, witb 10 perfect laterals. There are decided 

 side cusps and cuttiug points to centrals aud laterals; tbe transition to 

 tbe marginals is made as usual, the inner cutting point becoming bifid. 

 (Terr. Moll., V, Blate VIII, Fig. N.) 



Genitalia of both forms unobserved. 



DORCASIA, Gray. 



Animal beliciform, as in Patula. 



Shell moderately umbilicated, globose conoid or depressed-globose, 

 roughly striate; whorls 4A-5, the last large, globose, more or less de- 

 flected anteriorly; aperture Innate-ovate; ])eristome thickened, re- 

 flected, its columellar margin dilated and reflected. 



I hesitate to place our two species, Berlandieriana and griseola, in 

 this genus, on account of tbe geographical range of its species being 

 Australian, Indian, »S:c. 1 will, however, temporarily leave them here. 

 I do not believe they projjcrly belong to Frnticicola. 



D. griseola has a jaw slightly arcuate, high, ends scarcely attenuated, 

 ^''" '•27. blunt; cutting maigin without median projec- 



'fl \ I \\fYr-. tion; anterior surface entirely covered with 



numerous, about 12, broad, crowded ribs, den- 

 jii\\ ui- D.yfUtfoia. ticuiatiug either margin. Lingual membrane 



(Terr. Moll., V^, Plate VII, Fig. V) long aud narrow. Teeth about 27- 

 1-27, with 12 perfect laterals. Centrals with tbe base of attachment 

 long and rather narrow, the outer lower angles but little expanded, the 

 upper margin broadly reflected ; reflection large, with a very stout, 

 long median cusp, bearing a long, stout cutting point, extending below 

 the lower edge of the base of attachment ; side cusps obsolete, but side 

 cutting points present, large, triangular, acute. Laterals like the cen- 

 trals, but asymmetiioal by the suppression of the inner, lower lateral 



