42 University of California Publications in Zoology  [VoL. 23 
rounded, and equally produced with the spine. Right leg of second pair extends 
about to end of antennal scale; the left leg may be half again as long; the right 
carpus has nineteen to twenty-two segments, the left fifty-eight to sixty-three 
segments. Third segment of abdomen compressed and its posterior half carinated, 
the carina interrupted by a slight lobe at the posterior third of the segment; this 
lobe is of varying size, at no time strong, and has a tendency to disappear in 
large specimens, in which it may occur only as a slight unevenness in the curve, 
seen in profile; posterior margin well produced backward, rounded, unarmed; sixth 
segment of abdomen slender, about three times as long as wide. 
Dimensions.—Type, ovigerous female: length 124.5 mm., length of carapace 
and rostrum 59.5 mm., of rostrum 38 mm. 
Type Locality Off Santa Cruz Island, California, 155 fathoms (‘‘ Albatross’’ 
station 2949). 
Distribution.—From Unalaska to off San Diego, California, 25 to 199 fathoms. 
Remarks.—Distinguished from P. borealis (north Pacific and Atlantic), which 
has a similar rostrum, by the reduction of the abdominal lobe or hump and the 
absence of posterior median spines on third and fourth segments. 
‘ 
Biological Survey of San Francisco Bay.—Of the seventeen ‘‘out- 
side’’ stations, Pandalus jordan was taken at seven, D 5785-5791, 
representing all of those at which the depth exceeded 29 fathoms. At 
four of the stations from one to eighteen specimens were taken, from 
each of the other three more than fifty were obtained. With but one 
exception the bottom was ‘‘very fine, green sand.’’ From exceptional 
station, D 5791, very little bottom material was brought up other than 
‘‘refuse and garbage.’’ The ranges for temperature and salinity 
recorded at the time of making the various hauls were respectively 
9.38° to 12.2° C and 33.9 to 34.4. Crago alaskensis elongata also 
occurred quite abundantly at each of these stations. 
Pandalus montagui tridens Rathbun 
Plate 13, figure 2 
Pandalus montagui tridens Rathbun, Proc. U. S. Nat. Mus., 24, 901, 1902; 
H. A. E., 10, 41, pl. 2, fig. 2, 1904. 
Characters.—Rostrum slender, from one and one-half to one and four-fifths 
times the length of carapace. Dorsal spines ten to twelve in number, all movable, 
three to five on the carapace and the remainder on the basal half of the rostrum; 
posterior spine just in front of middle of carapace; inferior spines six or seven, 
rigid; distal two-thirds of rostrum ascending, tip trifid. Antennal scale with 
outer margin slightly arcuate; blade truncate at tip, spine stout, reaching to or 
beyond the end of blade. Right leg of second pair with carpus divided into twenty 
to twenty-eight segments. Left leg of second pair with carpus divided into about 
seventy-four segments. Sixth segment of abdomen slender, about three times as 
long as wide. 
