82 HOLOSPIRA. 



Arizona: Dos Cabezas. Two specimens and numerous frag- 

 ments were found in a cave in November, 1889, by V. Bailey, 

 U. S. National Museum, no. 104392. 



Holospira arizonensis STEARNS, Proc. U. S. Nat* Mus., xiii, 

 1890, p. 208, pi. 15, f. 2, 3; xiv, 1891, p. 100. H. (Eudi- 

 ftemma) arizonensis Stearns, DALL, Nautilus, ix, p. 50. 



About the size and figure of H. remondi, but differing from 

 .all other known species in the internal armature. 



Section Distomospira Dall, 1895. 



DALL, Nautilus, ix, p. 50 (Sept., 1895) ; Proc. U. S. Nat. 

 Mus., xviii, p. 3 ; xix, p. 346. 



Penultimate whorl with a short, stout lamella on the axis 

 and a weaker basal lamella only ; axis otherwise smooth, mod- 

 erately large and cylindrical. Type H. bilamellata Dall 

 {Distomospira, spire with two apertures, i. e., divided into 

 two cavities). 



8. H. BILAMELLATA Dall. PL 16, figs. 5, 10, 11. 



Shell elongate, slender, blunt-tipped, with two smooth nu- 

 clear and 15 subsequent whorls; the spire increases evenly to 

 the eighth whorl and then very slowly attenuate; sculpture 

 of slightly oblique, little raised, nearly straight riblets with 

 doubly wide interspaces marked by somewhat irregular lines 

 of growth; the sculpture between the ninth and the last 

 whorl is more or less obsolete, but on the last whorl is strong, 

 crowded, and a little irregular; suture distinct; base a little 

 appressed; umbilical chink small; aperture as in H. crossei, 

 but projecting beyond the periphery of the last whorl. Length 

 of shell 20.5, maximum diameter 5 mm. (Dall.) 



New Mexico: top of Hachita Grande Mountain, Grant Co. 

 (Dr. Mearns) ; with H. crossei, not uncommon; no. 129990, 

 U. S. N. M. 



Holospira (Distomospira) bilamellata DALL, Proc. U. S. 

 Nat. Mus., xviii, p. 4 (1895) ; xix, p. 349, pi. 31, f. 3 (1896). 



This species in form recalls H. semisculpta Stearns, but is 

 smaller, without the polished surface of the latter and of a 

 ferruginous white instead of the bluish color of H. semi- 



