MUSEUM OF COMPAKATIVE ZOOLOGY. 153 



snidothcr tlian above ; umbilicus very deep, reaching tbe apex, but only ex- 

 liiljiting the last three whorls, grooved within ; body whorl 

 gently ascending just behind the aperture, and then suddenly 

 and shortly deflected, very much constricted behind tlie peri- 

 stome, with two deep exterior pits, having the space between 

 them elevated into a prominent ridge ; aperture subtriangular, 

 peristome much thickened withhi and very sliglitly reflexed, 

 very tortuous, yellowish white, furnished with a small den- 

 tiido near its upper termination and an erect lamelliform tooth, 

 which is equal in length to about one fifth the diameter of 

 the base of the shell, extending from the lower end of the 

 uppermost pit almost to the inner edge of the body whorl ; low down in the 

 niDUtli of the shell there is, between this tooth and the denticle, a large white 

 tiingue-shaped, concave tooth ; and very near this, but rather lower down in 

 the luduth of the shell, and on the base of the body whorl, there is an oblique 

 stout, white tooth, which is sometimes slightly cleft on the edge. The parietal 

 wall, which is covered with a semi-transparent callus, bears a very strong, 

 arcuated, entering, white tooth, whose outer margins form almost a right 

 angle. 



Diameter, major, | inch ; minor, -^^ inch ; altitude, j inch. 



Eastern Texas. Mr. Jacob Boll. 



This species more nearly resembles Helix vultuosa, Gould, than any other 

 North American species, but differs from that shell in the shape and size of 

 the umbilicus and in the form and armature of the aperture, which in vultuosa 

 is lunate, almost circular, and in this species is rather V-shaped ; in vultuosa 

 the peristome, though moderately so, is decidedly reflexed, and its plane is 

 almost entirely unbroken ; in Ilenricttce it is very nuich thickened, but scarcely 

 at all reflexed, is very tortuous, and bears on its inner margin an obtuse den- 

 ticle and a long lamellilbrm erect tooth, which are wanting in vultuosa; in 

 Hmricttcc the two internal teeth are so far within the aperture as to be seen 

 only on looking into it, while in vultuosa they are plainly visible from the base 

 of the side ; in tbe latter the parietal tooth is arched npv:ards, and its outer 

 margin is rounded ; in Henriettas it takes the opposite direction, and its mar- 

 gins form almost a right angle ; the deep pits behind the peristome are want- 

 ing or obsolete in vultuosa. (Mazyck.) The species is referred to by Mr. 

 Bland in his "Eemarks," p. 116. 



To tlie original description of IMazyck I add a figure drawn by Mr. Arthur 

 F. Gray from the original specimen. As stated above, ]\Ir. Bland and myself 

 formerly considered this as a variety of T. vultuosa. It seems, however, quite 

 as worthy of specific weight as T. Cojjei. 



Triodopsis loricata, Gould, (p. 313.) 

 Mariposa Co., California. 



