246 MOLLUSCA. 
5. Bulimulus durangoanus, sp.n. (Tab. XV. figg. 11, 11 @.) 
Testa perforata, subelongata, irregulariter striatula, nitidula, alba, punctis et strigulis diaphano-griseis aspersa ; 
anfr. 6, primus et secundus subglobosi, verticaliter costulati, pallide fuscescentes, sequentes convexiusculi, 
sutura sat impressa, ultimus infra modice attenuatus ; apertura dimidiam longitudinem teste non eequans, 
paullum obliqua, ovata, superne acuminata, peristomate simplice, margine externo recto, tenul, arcuato, 
basali arcuato, columellari superne dilatato, reflexiusculo. 
Long. 15, diam. 6; long. aperture 63, latit. apert. 4 millim. 
Hab. N. Mexico: Villa Lerdo, in the State of Durango (Hoge). 
I have seen only one specimen of this species. The greyish semitransparent points 
or short streaks follow the lines of growth, but in the third whorl from above there are 
also some oblique streaks in the direction from above and behind to below and in front. 
B. durangoanus bears some resemblance to B. gruneri, Pfr., but is quite distinct from 
it in the different proportions of the whorls: if viewed from the side opposite to the 
aperture, the last whorl occupies half the length of the whole shell in B. dwrangoanus, 
somewhat less in B. gruneri; and the penultimate whorl, seen from the same side, 
equals nearly the length of all those which precede it in B. durangoanus, but much less 
in B. gruneri. The columellar margin of the aperture is somewhat inflated and 
twisted in B. gruneri, leaving a distinct depression between itself and the wall of the 
last whorl, whereas in B. durangoanus it is flatly dilated and joins the said wall quite 
plainly. Moreover, B. gruneri is uniformly white, without the greyish streaks and 
spots of B. durangoanus, but has, on the other side, the suture distinguished by its 
more opaque white colour. 
It approaches also somewhat the Californian B. artemisie, Gould, but is not so much 
elongated. So far as the general form of the shell is concerned, these two species may 
be placed in the subgenus Peronwus, Albers, which contains chiefly species living in 
arid regions. 
6. Bulimulus corneus. (Tab. XV. fig. 9.) 
Bulinus corneus, Sowerby, P. Z. 8. 1838, p. 37°. 
Bulimus corneus, Pfr. Monogr. Helic. Vivent. ii. p. 2197; in Martini & Chemnitz, Syst. Conch.-Cab. 
ed. 2, Bulimus, p. 242, t. 63. figg. 29, 30°; Reeve, Conch. Icon. v., Bulimus, t. 21. fig. 184° ; 
Angas, P. Z. S. 1879, p. 479° [not B. corneus, Lea (1837), see below, p. 248; nor of Michaud 
(1858), Deshayes (1833) (=grecus, Beck), or Menke (1830) (= beticatus, Fér.), the two 
latter being now referred to Buliminus]. 
Bulimus (Buliminus) corneus, Beck, Index Moll. p. 71 (1838) °. 
Bulimus (Leptomerus) corneus, Albers, Die Helic. ed. 1, p. 166%; Pfr. in Malak. Blatt. ii. p. 60 (1855) °. 
Orthalicus (Leptomerus) corneus, H. & A. Adams, Gen. Moll. ii. p. 156°. 
Bulimulus (Omphalostyla) corneus, H. & A. Adams, loc. cit. p. 161°. 
Bulimulus (Leptomerus) corneus, v. Mart. in Albers’s Die Helic. ed. 2, p. 222"; Fisch. & Crosse, 
Miss. Scient. Mex., Mollusca, i. p. 548”. 
Bulimulus corneus, Bland & Binney, Proc. Acad. Phil. 1873, p. 248”. 
Bulimus berendti (Pfr.), Tate, Am. Journ. Conch. v. p. 156 (1870)“*; Binney, Am. Journ. Conch. 
vii. p. 182 (jaw and radula) (1872) ». 
