46 BULLETIN 2 01, UNITED STATES NATIONAL MUSEUM 



BOREOMYSIS INERMIS (Willemoes-Suhm) 



Petalophthalmus inermis Willemoes-Suhm, 1874a, p. xv ; 1876a, p. 575. 

 Petalophthalmus armigcr Willemoes-Suhm, 1875 (female), p. 41, pi. 7, figs. 1, 



3-14. 

 Boreomysis scyphops G. O. Sars, 1884, p. 34 ; 1885, p. 178, pi. 32, figs. 10-20 — 



Calman, 1901, p. 23. 

 Boreomysis suhmi Faxon, 1893, p. 218, footnote. 

 Boreomysis distinguenda Hansen, 1908a, p. 100, fig. 2a-b. — Tattersall, 1913, p. 



869. 



Occurrence. — West coast of North America: Albatross stations 

 2839, 5 specimens ; 2860, 13 specimens ; 2919, 4 specimens ; 2927, 1 speci- 

 man; 2928, 1 specimen; 3071, 2 specimens; 3073, 2 specimens; 

 3074, 4 specimens; 3075, 2 specimens; 3126, 1 specimen; 3312, 16 

 specimens; 3343, 1 specimen; 3346, 2 specimens; 3348, 12 specimens; 

 4307, 4 specimens; 4317, 5 specimens; 4334, 2 specimens; 4337, 1 

 specimen; 4351, 2 specimens; 4353, 1 specimen; 4380, 2 specimens; 

 4389, 1 specimen; 4400, 1 specimen; 4401; 4 specimens; 4405, 3 speci- 

 mens; 4407, 3 specimens; 4415, 10 specimens; 4427, 2 specimens; 

 4428, 1 specimen; 4429, 4 specimens; 4516, 7 specimens; 4536, 4 speci- 

 mens; 4540, 2 specimens; 4541, 1 specimen. Bering Sea: Albatross 

 stations 3307, 6 specimens; 3607, 4 specimens; H3784, 8 specimens; 

 4781, 1 specimen. Sea of Okhotsk: Albatross station 5015, 1 

 specimen. 



Distribution. — This species has been recorded by Sars (1885) from 

 three localities in the South Pacific and by Tattersall (1913) from the 

 Weddell Sea. The long list of records here published shows that the 

 species, far from being a southern form, has a very extensive distribu- 

 tion in the deep waters of the Pacific as far north as the Bering Sea and 

 the Sea of Okhotsk. I have carefully examined all these specimens 

 and can find no characters on which they can be separated among them- 

 selves or from the published descriptions. The distribution rivals 

 that of other deep-sea species of Mysidacea, especially those belonging 

 to the genera Gnathophausia and Petalophthalmus. 



Remarks. — This species is very closely allied to B. scyphops G. O. 

 Sars, but as Hansen (1908a) has pointed out it differs in having the eye 

 more quadrangular in shape, with a thicker marginal rim. These 

 specimens agree with Sars' figure (1885, pi. 32, fig. 13) rather than 

 with Hansen's figure (1908a, p. 100, fig. 2) in that the dorsal rim of the 

 eye cup is not so thick as Hansen represents it. Otherwise there is the 

 closest agreement. 



The decision as to which name should be applied to this species 

 has been a matter of some difficulty. Willemoes-Suhm (1874a) ap- 

 plied the name Petalophthalmus inermis to a mysid from Challenger 

 station 147, and it is clear that the specimens so called were afterward 



