66 University of California Publications in Zoology [Vou. 23 
Dimensions.—Type: length 46.6 mm. 
Color.—Red (Owen). Almost transparent; red on the thorax in one ease, 
body streaked with brownish in another; still another with body violet and appen- 
dages deep pink; in a fourth instance the body had a light pink tinge. 
Type Locality—Monterey, California. 
Distribution—San Francisco Bay, California, to Magdalena Bay, Lower 
California. 
Remarks.—This species and the one following (S. brevirostris) are very similar 
in general appearance and are undoubtedly closely related. They can always be 
distinguished by the length of the antennal scale as compared with the telson; 
it is always longer than the telson in S. palpator; it may be equal, but never 
exceeds the telson in S. brevirostris, often falling short of it. S. brevirostris is 
relatively the much stouter and more robust species of the two, attaining also a 
much greater size. To emphasize these differences the following table, based on 
four of the largest specimens of each species in the U. 8. National Museum 
collections, is inserted. 
Length of Lengthof Length of 
All measurements Length of abdomen third antennal Length of 
in mm. Locality carapace (over all) mavxillipeds scale telson 
S. palpator San Pedro 8 17 12 + 3.5 
S. palpator Pacifie Grove 9 19 15 5 4.0 
S. palpator San Diego 9 19 20 5 4.5 
S. palpator San Diego 10 21 20 6 5.0 
S. brevirostris San Francisco Bay 14 28 37 it 7.0 
S. brevirostris Kadiak, Alaska 14 30 25 Th 8.0 
S. brevirostris San Francisco Bay 15 32 31 7 8.0 
S. brevirostris Unalaska, Alaska 17 35 43 8 8.0 
In eleven of a series of fourteen specimens of S. palpator, the tip of the 
rostrum had a simple ending, tip in one bifid and in two trifid. 
Spirontocaris brevirostris (Dana) 
Hippolyte brevirostris Dana, Proc. Acad. Nat. Sci. Phila., 6, 24, 1852; 
Crust. U. S. Expl. Exped., 1, 566, 1852, pl. 36, fig. 5, 1855. 
Heptacarpus brevirostris Holmes, Oceas. Papers Calif. Acad. Sci., 7, 198, 
pl. 3, figs. 50, 51, 1900. . 
Spirontocaris brevirostris Rathbun, H. A. E., 10, 99, 1904. 
a b 
Fig. 44. Spirontocaris brevirostris; a, lateral view of carapace; b, acicle 
(from Holmes). 
