1918] Packard: Molluscan Fauna from San Francisco Bay 331 
making the interstices appear as though covered with revolving, flat-topped 
ribs; sometimes these ribs are divided by an impressed line into pairs. Grayish 
brown, revolving ribs darker; aperture yellowish brown, ribbed within and 
stained darker in the interstices at the lip.’’ 
Carpenter (1863) reported this common intertidal species from 
this region. It was not taken by the Survey. 
Range.—Sitka, Alaska, to Monterey, California (Tryon). 
Chrysodomus tabulatus Baird 
Plate 37, figure 2 
Chrysodomus tabulatus Baird (1863), p. 66; Carpenter (1863), p. 663; 
Arnold, R. (1903), p. 228, pl. 7, fig. 6. 
Neptunea tabulata, Tryon (1881), p. 121, pl. 49, figs. 284, 286. 
Description.—Arnold (1903) described this species as follows: 
“*Shell large, fusiform; spire elevated; apex subacute; whorls eight, sharply 
augulated and keeled above, forming a rimmed spiral table; surface ornamented 
with revolving ridges of alternating size; suture very deeply impressed; aper- 
ture pyriform; outer lip thin, smooth; inner lip incrusted; canal long, narrow, 
eurved backwards; columella twisted, spirally ridged.’’ 
Length, 25 to 78 mm. 
Occurrence.—At station D 5789* (3, 1). 
This gastropod has not hitherto been reported from the vicinity 
of San Francisco. Several living specimens were dredged by the 
‘« Albatross’’ in the vicinity of the Farallon Islands at a depth of 46 
fathoms from a bottom composed of fine dark green sand. 
Range.—Strait of Juan de Fuea, Washington, to Catalina Island, 
‘alifornia (Cooper). 
NASSIDAE* 
Nassa Lamarck 
Nassa fossata (Gould) 
Plate 35, figures 12a and 12b; plate 57 
Buccinum fossatum Gould (1849b), p. 152; (1862), p. 67. 
Nassa fossata, Tryon (1882a), p. 55, pl. 17, figs. 316, 318; Wood and Ray- 
mond (1891), p. 57; Arnold, R. (1903), p. 232. 
Description —Arnold (1903) described this species as follows: 
“*Shell small, conical; spire elevated; apex subacute; whorls seven, convex; 
body-whorl ventricose; ornamentation of fourth and fifth whorl consists of five 
or six strong, nodose, spiral ridges which increase in number by intercalation 
on the lower whorls; the prominence of the nodes varies inversely with the 
number of ridges, the ridges on the body-whorl being nearly smooth and alter- 
nating large and small; the ridges near the angle of the whorl reach the greatest 
*Dall (1917, p. 575) has recently shown that the name Alectrion should be 
used for the ‘‘reticulate species (of Nassa) with little or no callus, no hump, 
. and simple or nearly simple outer lips .. .’’ 
