60 PROCEEDINGS OF THE ACADEMY OF [Feb. - 
Measurements of genitalia in millimeters. 
A, | 
st | ras} | ‘ 
= : ae 3 S 
2 \|2 | 4 EER aed Ny 
i a | sus a - BU 2d bale 
Eecolity a | $ |S88| | 2] ee | es | 28) 8 
5 pees SP eS ra eect ee 5 
py a a" & Pol wm. | Sead = 
Station 1, fig. 7......... 8 |4.5|6.5|0.6/14.5| 29 /|long| 23 | 94,328 
Station 3) fig. l..«:...:. 95 Bul"6 Veep ade sie wee hase 21 | 94,326 
Station 4, fig. 4.......... 7 Gy) 1b) Ctrae GU eae tr | camel he: | 19 | 94,325 
Nine-mile, fig. 2.......... 9 4.3 | 7 0.6 | 10 29 : 14 | 26 | 94,324 
: | 
In the alcoholic specimen from Nine-mile, the sole is tripartite by 
faint longitudinal impressed lines, with a median groove due to partial 
folding of the foot. There are transverse lines as shown in pl. III, 
figs. 3 and 6. The granulation above is fine and pebble-like as usual 
in Sonorella. The cesophagus is short, expanding into a large crop, 
on which the loose and open salivary glands lie. The liver is reddish 
purple. The buccal retractor and left ocular retractor are united in 
their posterior third, the tail and right ocular retractors being free 
to their common insertion. The lung is like that of Sonorella optata. 
In the specimens from Stations 3, 4 and 5, no longitudinal impressed 
lines could be traced on the sole. 
The jaw varies a good deal; a specimen from the type lot has six 
wide ribs. From Station 4 and Nine-mile the jaw has eight narrow 
ribs. 
All of the radule examined agree in having decidedly fewer teeth 
in a transverse row than S. hachitana flora or S. optata. 
Sonorella optata n. sp. PI. I, figs. 6-12, 17-19. 
The shell is umbilicate, umbilicus slightly less than one-seventh the 
diameter, similar to S. hachitana, Pale brown, fading to whitish 
around the umbilicus, encircled by a rather wide dark chestnut band 
above the periphery, bordered above and below with paler, whitish 
bands. The spire is low conic. Whorls 54, slowly increasing to the 
last, which is much wider, and descends deeply in front. The embryonic 
shell consists of 14 whorls. The first half whorl has radial wrinkles, 
and begins in a smooth tip; then a small areolate area follows, after 
which there are curved, forwardly descending delicate threads reaching 
the suture below, but weak or obsolete on the summit of the whorl, 
which is irregularly roughened ; there are also some forwardly ascending 
threads in places. The first neanic whorl has sculpture of slight 
growth ripples and an indistinct roughening or punctation. Subse- 
