190 BULLETIN 2 01, UNITED STATES NATIONAL MUSEUM 



at the base, armed with two pairs of spines, the inner much shorter 

 than the outer, lateral margins armed with from 13 to 21 spines not 

 arranged in series but regularly spaced and increasing gradually in 

 size, posterior to the three large spines at the base, from the anterior 

 to the posterior end. (6) Fourth pleopod of the male (fig. 73, b) with 

 the distal joint of the exopod slightly more than half as long as the 

 proximal joint, terminal setae less than half as long as the distal 

 joint. 



This species is very closely related to N. awatschensis (Brandt), 

 but it may be distinguished by the following characters : 



(1) The rostral plate is broadly rounded whereas in N. awatschensis 

 it is pointed and triangular. (2) The eye is relatively smaller. (3) 

 The antennal scale is relatively longer. (4) The telson is slightly 

 longer in proportion to the breadth at the base, the spines on the lateral 

 margins are somewhat fewer and appear to be less crowded together. 

 (5) The fourth pleopod of the male has the distal joint of the exopod 

 much longer, about half of the proximal, whereas in N. awatschensis 

 it is only about one-quarter of the proximal joint. 



The specimens here referred to N. intermedia agree closely with the 

 description and figures given by Czerniavsky, except for the fourth 

 pleopod of the male. It is almost certain that Czerniavsky's male 

 specimens were immature. Both Dershavin and I had previously re- 

 corded this species under the name TV. awatschensis but examination 

 of true specimens of the latter species enables me to correct the error. 



NEOMYSIS AWATSCHENSIS (Brandt) 



Figure 74 



Mysis awatschensis Brandt, 1851, p. 126. 



Neomysis awatschensis Zimmer, 1904, p. 468, fig. 163. — Tattersaix, 1932b, p. 



321.— UeNo, 1933b, p. 188, fig. 8.— Miyadi, 193Sb, p. 240. 

 Neomysis nigra Nakazawa, 1910, p. 248, pi. 8, figs. 3, 17, 30. — Tattersall, 1921, 



p. 410, pi. 15, figs. 5-6.— Miyadi, 1933a, p. 27. 



Occurrence. — Japan : No specific collection data ; large numbers of 

 both sexes ; Yatabe, No. 33, A. S. Pearse collector, June 22, 1929, many 

 specimens of both sexes. 



Distribution. — This species is abundant in brackish water in China 

 and Japan, where it occurs in company with N. intermedia. It has not 

 yet been recorded from eastern Asiatic Russia. 



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

 acters: (1) The carapace is produced into a broadly triangular ros- 

 tral plate with a pointed apex. (2) The eye is slightly less than iy 2 

 times as long as broad, the peduncle is half as wide as the eye is long, 

 and the cornea occupies half the entire eye. (3) The antennal scale 

 (fig. 74, a) is about eight times as long as broad. (4) The sixth joint 



