150 _ PROCEEDINGS OF THE ACADEMY OF [March, 
Zonitoides singleyana (Pils.). 
Zonites singleyanus Pils., Proc. A. N.S. Phila., 1889, p. 84; 1888, pl. 17, fig. 
M. (New Braunfels). 
Hyalinia leviuscula Sterki, Nautilus, VI, p. 53, Sept., 1892 (New Braunfels). 
Texas: San Marcos, New Braunfels, Del Rio, Devil’s river and Pecos 
river above the High Bridge; everywhere in river débris. 
Arizona: Drift of San Pedro river at Benson. 
Zonitoides nummus Vanatta. 
Proc. A. N.S. Phila., 1899, p. 524, figs. (New Braunfels). 
This species seems to be confined to the Texan Lower Sonoran. We 
took it at San Marcos, Hays county; Guadalupe river above New 
Braunfels; Hondo river, Medina county; and in Val Verde county 
near Del Rio; along the Devil’s river, and in the Pecos canyon above 
the High Bridge; everywhere in drift débris. 
Zonitoides arborea (Say). 
Texas: Galveston; Smithville, Bastrop county; Sinking Spring, near 
San Marcos, Hays county; near New Braunfels, Comal county. 
New Mexico: Drift of Pecos river at Pecos (Cockerell). 
Arizona: Cave creek canyon and Bear Park, Chiricahua mountains, 
Cochise county. 
Vitrea indentata (Say). 
Drift of Pecos river, Pecos, New Mexico (Ckll.). As usual, it is the 
Canadian and Carolinian form of the species which extends down the 
Rocky mountains into New Mexico, and not the Sonoran subspecies. 
Vitrea indentata umbilicata (‘Singl.,’ Ckll.). 
Ckll., Nautilus, XII, p. 120, Feb., 1899. 
Texas: San Marcos, Hays county; around New Braunfels, Comal 
county; Hondo river two miles north of Hondo, Medina county; Del 
Rio, Devil’s river and Pecos river at the High Bridge, Val Verde county; 
Alpine, Brewster county, 
Arizona: Cave creek canyon and Bear Park, Chiricahua mountains; 
Fort Bowie. Also Florida mountains, Grant county, New Mexico. 
Large specimens of this race are probably what has been reported from 
Texas as sculptilis Bld.,—a species which does not, we believe, occur in 
that State. 
This Sonoran race differs from indentata by its distinctly perforate 
axis and larger average size, yet the perforation varies so much in 
size in specimens from the Carolinian zone that I would not myself 
have named the Southwestern form. The name is ill-chosen, since the 
shells are not ‘‘umbilicate,’’ as that term is technically used, but ‘‘per- 
forate.’’ 
