290 University of California Publications in Zoology — [Vou. 14 
marked only by growth lines which in crossing it are elevated into sharp ribs, 
in which character they are continued to the anterior margin. The posterior 
of the shell anterior to the radiating furrow is ornamented with numerous 
longitudinal ribs, approximating in pairs and rendered acutely scabrous at the 
intersections of the rib like growth lines. 
Ventral anterior margin emarginate. Dorsal anterior margin reflected and 
closely appressed over the beaks. Posterior dorsal margin declining somewhat 
to the quadrately rounded posterior lateral end. Color white.’’ 
Length, 12 to 120 mm. 
Occurrence.—At stations D 5709 (f.), D 5711 (f.), D5712* (f£.), 
D5sil3 (£), Dsl (2), Ds723 (2), D539 (1), DdbT40)G@). D 5142 
(f.), D 5755 (f.), D 5764* (2), D 5767 (1), D 5796 (£.), D 5802 (2), 
D 5808 (f.), D 5809 (£.), D 5821 B (f.), D 5824 (2), D 5824 B (f.), 
D 5825 (13), D 5825 B (1), D 5826 (1), D5826 A (f.), D 5827 (1), 
D 5827 A (2), D 5827 B (f.), D 5828 B (10, 10), D 5831 (7, 3), D 5833 
(f.), D 5835 (f.), D 5836 (1), D 5839 (3), D 5841 (4), D 5842 (6), 
D 5843 (2), and questionably at D 5710, D 5778, Standard Oil Pier, 
Richmond. 
This species is represented in the Survey collections by a number 
of old shells, which were taken within the middle division of the bay. 
Living specimens were dredged at two stations at depths of 1014 and 
13 fathoms. 
Range.—Bering Sea to San Diego, California. 
TEREDINEDAE 
Xylotrya Leach 
Xylotrya, sp. 
Wood perforated by teredo borings was dredged at stations D 5700, 
D 5702, D 5709, D 5735, D 5766, D 5777, and 5808. Wood and Ray- 
mond (1891) report the species Y. setacea from San Francisco Bay, 
which is undoubtedly the species living within these waters. 
SCAPHOPODA 
DENTALIIDAE 
Dentalium Linnaeus 
Dentalium indianorum Carpenter 
Dentalium indianorum Carpenter (1863), p. 648. 
Dentalium pretiosum Nuttall var. indianorum, Pilsbry and Sharp (1897— 
1898), p. 45, pl. 13, figs. 4, 5, 6, 8; Arnold, R. (1903), p. 186, pl. 8, fig. 4. 
Description.—Arnold (1903) described this species as follows: 
‘*Shell small, curved, tapering posteriorly, heavy; surface with fine incre- 
mental rings, and striated posteriorly; cross-section and aperture circular.’’ 
Length, 10 to 25 mm. 
