1906. ] NATURAL SCIENCES OF PHILADELPHIA. 157 
of ‘‘bad letters.’’? All authorities agree that such obvious typograph- 
ical errors should be corrected. 
Helicodiscus eigenmanni Pils. Pl. VIII, figs. 1, 2, 3. 
Nautilus, XIV, p. 41. August, 1900 (Beaver cave, near San Marcos, Texas). 
This fine species is easily recognized by its large size, the shell in 
all stages of growth being very much more robust than H. parallelus. It 
~ is sculptured with numerous spiral threads as in H. parallelus, and 
when fresh is pale yellow. Alt. 2, diam. 5 mm., with 54 whorls. 
We took specimens in the drift débris of Sinking creek at San Mar- 
cos, Hays county; on the Guadalupe river above New Braunfels, 
Comal county; on the Hondo river, Medina county, and in the drift 
of Devil’s river, Val Verde county; Alpine, Brewster county. I have 
seen specimens also from Calhoun county (Hubbard), Lee county 
(Singley), and Navidad river bottom, Jackson county (J. D. Mitchell). 
It has not been reported from any place out of Texas, and seems to 
have about the same distribution as Holospira goldfussv. 
Helicodiscus eigenmanni arizonensis n. subsp. PI. VIII, figs. 4, 5, 6. 
Shell larger than H. parallelus with 44 to nearly 54 whorls, the spire 
flat or convex, the umbilicus wider than in parallelus or eigenmanni. 
Surface closely and strongly lirulate spirally. Aperture oblique, lunate, 
very small. 
Alt. 2, diam. 5 mm., whorls 53. (Fort Bowie.) 
Alt. 1.5, diam. 4.6 mm., whorls 44. (Cave creek canyon.) 
Arizona: Fort Bowie (type locality); Bear Park and Cave creek 
canyon, Chiricahua mountains; Huachuca mountains (Ferriss); Santa 
Rita mountains (Ashmun). New Mexico: Florida mountains, Grant 
county (Ferriss); Bland, Sandoval county (Ashmun); débris of Arroyo 
Pecos at Las Vegas (Ckll.). 
Readily distinguished from H. parallelus when mature by the greater 
size, with wider umbilicus, more whorls and proportionately smaller 
mouth. Some specimens are two-toothed. H. eigenmanni has a 
smaller umbilicus, whorls of markedly greater calibre and a larger 
aperture. 
Helicodiscus salmonensis (Hemphill). 
Helicodiscus fimbriatus Wetherby (salmenacca Hemphill), W. G. Binney, 
Third Supplement to Terr. Moll., V, Bull. Mus. Comp. Zool., XIX, No. 4, 
p. 189 (May, 1890). 
Helicodiscus fimbriatus var. salmonensis Hemphill, in Binney, t. c., p. 220 
(May, 1890). 
Helicodiscus fimbriatus Wetherby, var. salmonaceus Hemphill, Binney, 
Fourth Supplement, Bull. Mus..Comp. Zool., XXII, No. 4, p. 177, pl. 3, 
fig. 8. 
Distinguished by the absence of spiral striz, according to Hemphill. 
