258 PROCEEDINGS OF THE ACADEMY OF [Mch., 
mm., width of umbilicus 4.7 mm., or even larger 29.5x 15.5 mm. 
They exceed 8. ashmuni Bartsch in size, and are larger than any Sono- 
rella on record (Pl. XVII, figs. 1,2). The aperture is ample, 12.9 x 14.5 
mm. 
Another lot (86,496, A. N.S. P.), figured on Pl. XVII, figs. 3-6, from 
the same locality, consists of smaller specimens. Some are typical 
hachitana in form and size except that the last whorl descends more 
deeply in front, making the aperture subhorizontal in some specimens 
(figs. 5, 6). In a few specimens the supraperipheral band is almost 
obsolete, very narrow and interrupted (figs. 3, 4), but most of them are 
pale reddish-brown, fading to white in the middle region of the base, 
and with a white or whitish band on cach side of the dark supra- 
peripheral belt. 
Alt. 14.5, diam. 25.4, width of umbilicus 4 mm. 
6c“ 14.3, “ee 27 .t, cc cc 4 ce 
oe 13 “ 26.7, “ce co 3.9 ce 
cc 13.9, cc 26, “c ce 4 cc 
ce 13.7, ‘cc 26, cc “c 3.9 ce 
“ch 13.3, ce 23.5, cc cc 3 cc 
SU 2 ee Ban) 2:0 
c 126; ce oD (a3 “cc 3.9 (a3 
cc 10.7; ce 22, ‘cc ce 3.8 a3 
Specimens of this lot were sent alive. 
The pale sole is indistinctly tripartite, extremely weak impressed 
lines dividing it in some specimens, not traceable in others. The back 
is slate or blue-blackish, the tail brown above, paler toward the foot- 
edges. The surface is finely pebble-granulate. There is a pair of 
indistinct dorsal grooves, and the genital furrow is traceable only near 
the mantle. The tail is depressed, with a very faint median groove. 
The genitalia (Pl. XX, fig. 12) show no differences of any moment 
from the form of hachitana from Purtyman’s ranch, Arizona, figured 
by me in 1900, except in the shape of the spermathcea, which, however, 
is not constant in the Purtyman’s lot. The individuals examined were 
partly not fully developed, and possibly older specimens will show a 
somewhat stouter vagina and penis than that figured. The penis 
papilla is long and slender, not convoluted in the specimen opened. 
The jaw (Pl. XXIII, fig. 20) has eight ribs. 
The radula is somewhat unlike other Sonorellas examined in the 
central tooth, which is narrower than the adjacent laterals. There 
are 55.1.55 teeth, an ectocone appearing on the fifteenth. Both cusps 
are bifid on most of the marginal tecth, the mesocone +entocone being 
