126 PROCEEDINGS OF THE ACADEMY OF [March, 
Braunfels, Comal county; San Antonio, Bexar county; Hondo river, 
two miles north of Hondo, Medina county; Del Rio, Val Verde county. 
Mr. Ferriss took some thin, translucent specimens, 8x 10 mm., at 
Smithville. The shell varies from 9.8 to 11.7 mm. diam. The pub- 
Fig. 2. 
lished figures do not show that there is frequently a short lamellar 
tooth or callous on the parietal wall near the suture, a short distance 
within, as shown in the figured specimen from the Guadalupe river 
near New Braunfels. 
Thysanophora hornii (Gabb). 
Texas: Hondo river, near Hondo, Medina county; Rio San Filipe, 
near Del Rio; Devil’s river, west of Del Rio, and Pecos river at the 
High Bridge, Val Verde county, all in river drift. 
New Mexico: Florida mountains, near Deming, Grant county. 
Arizona: Cochise county; Cave creek canyon in the Chiricahua 
mountains; Fort Bowie; drift of San Pedro river at Benson, and 
Manilla mine, at the west end of the Huachuca mountains. 
This small species is a typical Thysanophora, closely related to the 
type of the genus. It varies but little throughout its extensive range, 
unless it be in the cuticular lines and hairs, which are worn off of the 
river-drift specimens. It has not before been reported in this country 
from east of Cook’s, Grant county, N. M. Our collection of 1903 
extended its known range in the United States more than 500 miles 
eastward, to the border of the Staked Plains in central-southern 
Texas. Further localities in Arizona are given in Nautilus, XII, p. 99. 
In Mexico, 7. hornii has been collected at Topo Chico, near Mon- 
terey, Nuevo Leon, and at Victoria, Tamaulipas (Proc. A. N.S. Phila., 
1903, p. 763). It is therefore one of the widely distributed species of 
the States both north and south of the international boundary in 
the Sonoran area. 
Polygyra auriformis (Bld.). 
Helix aurijformis Bland, Ann. Lyc. Nat. Hist. of N. Y., VII, p. 37 (1858). 
? Helix sayii Wood, Index Testaceologicus, Suppl., p. 22, pl. 7, p. 34 m (1828). 
Texas: Galveston (J. H. Ferriss); Calhoun county (Hubbard) ; 
