1906. ] NATURAL SCIENCES OF PHILADELPHIA. 129 
sometimes concealed in the shelter of the downward-drooping dead 
leaves on standing Yuccas. From this region they have been washed 
into the Devil’s river, where bleached shells are abundantly found in 
the drift débris. 
We also took specimens in the high land along the Pecos river, near 
the High Bridge (Viaduct, on some maps), east of the river, and in 
drift débris in the canyon. 
In the interior counties of Texas we took specimens in the drift of 
the Hondo river, Medina county, about two miles north of Hondo. 
Much farther northward Mr. Ferriss found hyperolia at Colorado 
City, Mitchell county, Texas. 
In New Mexico Prof. J. D. Tinsley collected it on South Spring 
creek, near Roswell, in the Pecos valley, where it occurred fossil in a 
bed of white marl, three to four feet below the surface. It is not now 
found living in that locality. We are indebted to Prof. Cockerell for 
these specimens.’ 
P.t. hyperolia varies about as much as texasvana in size. Specimens 
from west of Devil’s river measure from 3.8x8 mm., with 44 whorls, 
to 4.2x11 mm., with 5 whorls. 
This variety is not the Helix (Polygyra) tamaulipasensis of Lea, 
which is typical P. texasiana, as I have ascertained by a comparison 
of the type kindly made for me by Dr. W. H. Dall. 
Polygyra texasiana texasensis (Pils.). PI. V, figs. 11, 12. 
Polygyra texasensis Pils., Nautilus, XVI, p. 31, July, 1902. 
Similar to P. t. hyperolia in the depressed shape and smooth surface, 
without riblets above; but decidedly larger, with about 54 whorls, 
the umbilicus broader than is usual in the other forms of the species. 
Alt. 5.2, diam. 12.5 mm. 
Alt. 5.8, diam. 12.5 mm. 
Alt. 5.8, diam. 13.7 mm. 
Colorado City, Mitchell county, Texas; types collected by James H. 
Ferriss in 1902, No. 83,258, A. N.S. Phila. 
This is a large edition of P. t. hyperolia, and further collections from 
the almost unknown northwestern half of Texas are needed to deter- 
mine whether it is really distinct enough from that subspecies to call 
for recognition of the latter by name. In the large series of hyperolia 
collected there were, however, no forms as large as texasensis. 
Polygyra mooreana (W.G. Binn). Pl. V, figs. 4-10. 
This species stands close to P. texasiana, but the shell is smaller than 
7 Reported as P. triodontoides in The Nautilus, XIII, November, 1899, p. 84. 
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