CLASS GASTROPODA 
15 
Alabina tenuisculpta phalacra Bartsch, 1911 
Plate 96, fig. 5 
Proceedings of the United States National Museum, 39:417; PI. 61, fig. 5. 
Shell broadly elongate-conic, light chestnut brown. Nuclear whorls 
2*4, small, increasing regularly in size, smooth. Post-nuclear whorls 
slightly shouldered at the summit, marked by slender, axial ribs, of 
which 18 occur upon the first to fourth, 20 upon the fifth and sixth, and 24 
upon the penultimate turn. Upon the early whorls the ribs are almost verti¬ 
cal ; on the last two they are decidedly retractive. Here also they are less 
regular. In addition to the axial ribs, the whorls are marked by three 
obsolete spiral cords, of which one is median, another a little nearer to the, 
median cord than the summit, and the third about halfway between the 
median and the suture. Periphery and base of the last whorl inflated, the 
latter narrowly umbilical, marked by five subequal subobsolete cords. The 
space immediately about the umbilical area is smooth. Aperture very 
broadly ovate; posterior angle obtuse; outer lip thin, showing the external 
sculpture within; columella slender, curved, and slightly revolute; parietal 
wall glazed with a thin callus. Length, 7.5; diameter, 3 mm. (Bartsch.) 
Type in United States National Museum, No. 32205a. Type locality, 
San Diego, California. 
Range. Known only from type locality. 
Alabina diegensis Bartsch, 1911 
Plate 96, fig. 4 
Proceedings of the United States National Museum, 39:416; PI. 61, fig. 4. 
Shell elongate-conic, chestnut brown, excepting the extreme apex and 
the last volution, which are paler. Nuclear whorls three, small, increasing 
regularly in size, well-rounded, without sculpture. The early post-nuclear 
whorls have a decidedly sloping shoulder which extends from the middle 
to the whorls, between the sutures to the summit. This shoulder is marked 
on the first whorl by a single cord that limits it anteriorly, on the second 
by an additional cord, which divides the shoulder in two equal halves, 
while on the third, two additional cords, a little less strong than the other 
two, divide the space between the summit and the first cord and the space 
between the next two cords into equal halves. The sculpture on the 
anterior half of the whorls between the suture consists of a single cord 
on the first and second, which is halfway between the median cord and 
the suture. On the third, an additional cord a little less strong appears 
between the two. This cord becomes equal in strength to the other two 
on the succeeding turns. The space between the suture and the first supra- 
sutural cord remains plain, barring exceedingly fine microscopic spiral 
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