198 BULLETIN 201, UNITED STATEIS NATIONAL MUSEUM 



NEOMYSIS MIRABILIS (Czemiavsky) 



Figure 78 



Heteromysis mirabilis Czerniavsky, 18S2b, p. 33 ; 1887, p. 84, pi. 20, figs. 1-17. 

 Neomysis mirabilis Zimmer, 1904, p. 468, figs. 161, 162. — Dershavin, 1913, p. 197. — 



Birstein, 1939, p. 56, figs. la-c. 

 fNeomysis andersoni W. L. Schmitt (pars), 1919, p. 6 (juv. fig. 3a). 

 Neomysis nakazaioai Ii, 1936a, p. 581, figs. 3-13. 



Occurrence. — Siberia : Bering Island, from mouth of cod, N. Greb- 

 nitzky collector, 1 adult female ; No. 2539, 1882-83, L. Stejneger col- 

 lector. Commander Islands : No. 2462, 1882-83, L. Stejneger collector, 

 1 immature female; Petropavlovsk-Kamchatski^ 1883, N. Grebnitzky 

 collector, 1 adult breeding female, 20 mm., 100 mostly immature males 

 and females, 12 to 15 mm., but some of the females breeding at 15 mm. ; 

 L. Stejneger, 1882-83, collection numbers 2624, 1 immature male ; 2630, 



5 adult females, 9 immature females and 8 males, 15-16 mm. ; 2631, 



6 adult females, 11 immature females and 24 immature males, 15 to 16 

 mm.; 2633, 2 immature specimens; Albatross collector, 1906, 77 breed- 

 ing females, largest 30 mm., 5 males, largest 25 mm. Japan : Mororan, 

 shore, Albatross collector, July 6, 1906, 75 adult breeding females; 

 Albatross station 5003, 2 adult females. Alaska : Grantley Harbor, 

 Port Clarence, August 3-4, 1913, at surface, 2 immature. 



Distribution. — Gulf of Castries, Asiatic Russia (Czerniavsky, 

 1882b) ; (Dershavin, 1913) ; Kamchatka (Dershavin, 1913) ; Sagha- 

 lien, Japan (Ii, 1936a). The present material is mainly from Asiatic 

 Russia and Petropavlovsk, but it includes a large number of specimens 

 from Mororan, Japan, and two immature specimens from Alaska. 



Remarks. — This species may be distinguished by the following char- 

 acters: (1) The last thoracic somite is furnished with well-marked 

 furrows and ridges; these are much less marked on the first three 

 abdominal somites and quite incipient on the fourth and fifth ab- 

 dominal somites. (2) The carapace is produced into a quadrangular 

 rostral plate with rounded angles, front margin somewhat concave; 

 rostral plate leaves the eye and antennules completely uncovered. 

 (3) The eye, including the eyestalk, is about iy 2 times as long as 

 broad with the cornea occupying about one-third of the eye in dorsal 

 view. (4) The antennal scale (fig. 78, a) is 12 to 15 times as long as 

 broad. (5) The sixth joint of the endopods of the third to the eighth 

 thoracic limbs is divided into 9 to 15 subjoints. (6) The telson (figs. 

 78, c } d) is about 2y 2 times as long as broad at the base, linguiform in 

 shape with sinuous lateral margins and a narrowly rounded apex; 

 lateral margins armed with 40 to 50 stout blunt spines, which in the 

 proximal part of the margins are somewhat widely spaced, in the 

 central part of the margins arranged in groups of two to four smaller 

 spines between rather larger spines, and in the distal third of the 



