62 RATHBUN 



but there is some individual variation. The usual number of spines is 



one on the second and sixth segments and two on each of the other 



segments. 



Distributio7i. — Arctic coast of America; Bering Sea to Puget Sound; 



Kamchatka ; Okhotsk Sea ; Atlantic coast of America from Greenland 



to Narragansett Bay, Rhode Island, 1-72 fathoms: 



Berg Bay, Glacier Bay, Alaska (Harriman Expedition). 



Dredged by the Albatross from off Cape Menshikof, Bering Sea, to the 

 Aleutian Islands and Portlock Bank, Alaska, in 16 to 72 fathoms; at 

 the unusual depth of 283 fathoms, off Seguam, Aleutians, a lot of 

 large specimens, the largest $ measuring 77 mm., the largest 567 mm. ; 

 Strait of Fuca and Puget Sound, 40-48 fathoms; off Kamchatka, 

 12 and 42 fathoms, stations 3780 and 3781 ; Avacha Bay, Kamchatka, 

 16 fathoms, station 3642; Rakovaya Bay, Avacha Bay; off Robben 

 Island, Okhotsk Sea, 10 fathoms, station 3645. 



Various localities from Kadiak westward along the Aleutian Islands, in 

 3-25 fathoms (W. H. Ball). 



Puget Sound (T. Kincaid). 



Avacha Bay and Petropavlovsk, Kamchatka (L. Stejneger). 



Bering Island, among Laminaria, and Solovarennaja Bay, Petropavlovsk, 

 Kamchatka, 10-12 fathoms (N. Grebnitzky). 



Arctic Ocean (Stimpson). 



SPIRONTOCARIS LAMELLICORNIS (Dana). 



Hippolyte lamellkornis'DPi.^k, Proc. Acad. Nat. Sci. Phila., 1852, 24; Crust. 



U. S. Expl. Exped., I, 567, 1852, pi. xxxvi, fig. 6, 1855. — Stimpson, 



Jour. Boston Soc. Nat. Hist., vi, 498, 1857. — Kingsley, Bull. Essex 



Inst., X, 62, 1878. 

 Spirontocaris lamellicornis WALKER, Trans. Liverpool Biol. Soc, xil, 277, 



1898. — Holmes, Occas. Papers Calif. Acad. Sci., vii, 208, 1900. 



This species, though resembUng strongly S, spina, is at once separated 



by the acuteness of the lateral margins of the first to third abdominal 



,;«-^.^^ segments, which in S. spina are broadly 



y^"*^"""^""^ ^^^ rounded. The rostrum is about three 



.^'i^*-^^ ^S fourths as long as the rest of the cara- 



*-^ ^ ) pace, and does not exceed the antennal 



'^^•>,,.^^^ ^^^^ scale, although it may exceed the blade 



Fig. 18. spirontocaris lanteiiicornis. Side of the scale. The spiuc of the scale ex- 



ofcarapaceof ?(Xxi). Station 3046. ^^^^^ htJOUdi the blade tO a distance 



equaling or exceeding the distal width of the blade. The dactyli of the 

 last three pairs of feet are longer than in S. spina, those of the last pair 

 being half the length of their propodi ; they are armed with spinules so 

 minute that the segment appears entire in comparison with S. spina. 

 Dimensions.— $ , length 63 mm., carapace 23 mm. 



