386 A MANUAL OF AMERICAN LAND SHELLS. 



one of tbe former. Cabinet of Dr. Levette, and the Binney and Bland 

 collection in tbe American Mnseura of Natural History, New York. 



This species is quite distinct from any known North American or 

 other form. The number of whorls and of teeth, their form and color, 

 with the color of the shell and peristome, are its peculiar features. The 

 stride are by no means so well developed as shown in the figures. 

 (Bland.) 

 Tiiodopsis Levettei, Bland, Ann. Ac, Sc. N. Y., ii, 115, fig. (1880). 



The above is a coi)y of Bland's description and figures ; I hardly 

 kJiow to what region the species may be said to belong. 



Lingual membrane as usual in the genus; teeth 25-1-25. 



The species varies in the number of teeth on the peristome. Some 

 have one basal tooth only, which in some specimens is widely and 

 bluntly bifid. 



TRIODOPSIS. (See p. 283.) 



Trio<]o|>«»i!>« vulHiosa, Goui.d. 



Shell umbilicated, orbicular.-depressed, about equally convex on both 

 sides, rather solid, dark horn-color, delicately striated; spire 

 a low dome, composed of about 5^ whorls, which are mod- 

 erately convex and separated by a well-defined suture, the 

 exterior one somewhat angular at periphery ; beneath well 

 rounded and i)erforated by a deep umbilicus about one- 

 T ruituoK.',. fourth as broad as the base; aperture rather large, lunate; 

 peristome moderately reflexed, tortuous, white, having at the base a 

 small tooth and at the center a deeply seated, more expanded, reflexed 

 tooth ; the parietal wall bears a stout, elevated, arcuated, oblique 

 lamella, joined to the lower extremity of the peristome only ; on the 

 base of the shell is a transverse internal tubercle. Greater diameter 

 10, lesser 0"™; height, 5h""^. 



Helix viiltiiosa, Gould, Pr. Bost. Soc. Nat. Hist., iii, 39 (1848); in Terr. Moll., ii, 189, 



pi. xl,a, fig. 4.— Rkeve, Con. Icon., No. 711 (1852).— Pfeiffer, Mon. Hel. 



Viv., iii, 2();5; in Chemnitz, od. 2, iii, 305, pi. cxxvii, tigs. 10, 12.— \V. G. 



Binney, Terr. Moll., iv, 75; L. & Fr.-W. Sh., i, 133 (1869).— Bland, Ann. N. 



Y. Lvc.vii, 439, pi. iv, fig. 21. 

 Triodopsis vultnosa, Tryon, Am. Journ. Conch., iii, 53 (1867).- W. G. Binney, Terr. 



Moll., V. 



Arkansas and Texas; a species of the Texas Subregion. 



Jaw with 12 ribs. 



Lingual mend)rane as in the genus ; 20-1-20 teeth, with 11 laterals. 



The form of this species described and figured by Bland {I. c.) has 



