150 PROCEEDINGS OF THE ACADEMY OF [March. 



Zonitoides singleyana (Pils.)- 



Zonites singleyanus Pils., Proc. A. N. S. Phila., 1SS9, p. 84; 1888, pi. 17, fig. 



M. (New Braunfels). 

 Hyalinia Iceviuscula 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; ever}n\'here in river debris. 

 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 debris. 

 Zonitoides arborea (Say). 



Texas: Galveston; Smith ville, 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). 

 CkU., 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 Bid., — a species which does not, we believe, occm- 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. ' ' 



