MYSIDACEAN CRUSTACEANS — TATTERSALL 537 



directed spine on each side posterior to the eye and just in front of 

 the cervical sulcus. In pacificus this spine is replaced by a thick 

 blunt protuberance. 



Curiously, Ortmann made no reference to these characters when 

 recording the Japanese specimens. A reexamination of his specimens 

 reveals, however, that in these characters they agree precisely witli 

 L. pacificus, and Fage himself stated that they belong to this species. 



Tattersall (1951) founded anew species, L. japonicus, on specimens 

 captured by the Albatross in 1906 off the south of Japan and, at the 

 same time, expressed the opinion that the Japanese specimens referred 

 by Ortmann (1906) to L. typicus should be referred to it. The types 

 of japonicus agree in every detail with Ortmann's material including 

 tho presence of only three teeth (or in one case oidy two) on the outer 

 margin of the antenna! scale. 



After very close examination of all the material of japonicus in the 

 collections of the U.S. National Museum — amounting to 13 cf and 

 7 9 (3 ovigerous) — I can find no other constant point of difference 

 between these specimens from Japanese waters and the description 

 and figures given by Fage of his types of L. pacificus. Since in other 

 species of the genus the number of teeth arming the antenna! scale 

 is somewhat variable, I think that L. japonicus should be referred 

 to the synonymy of L. pacificus. 



In his description of L. pacificus, Fage did not mention any armature 

 on the lobe from the anterior margin of the antennular peduncle. 

 He simply stated, as one of the characters of the species, "ecaile 

 antennulaire largement deprimee an bord anterieur." 



Lophogastcr hawaiensis Fage 



Figure 4 



Lophogaster hawaiensis Fage, 1942, p. 30, figs. 



Lophoqaster typicus, Ortmann, 1905, p. 967; 190G, p. 23 (Hawaiian specimens only). 



Occurrence: Albatross stations 3847, 3857, 3858, 3884, and 4101 

 situated in coastal waters around the Hawaiian Islands; two specimens 

 taken at 43 m. but the remainder around 250 in. in depth. 



Remarks: This species very closely resembles L. intermedins in 

 the presence of minute scattered nodules or microscopic blunt spinules 

 on the carapace, in the length and shape of the rostrum, and in the 

 shape and armature of the telson. It can be distinguished from 

 intermedins by its relatively broader antennal scale with its somewhat 

 convex outer margin and much more convex inner margin, by the 

 characteristic concave anterior margin of the antennular lamina, and, 

 if the specimens from the Mergui Archipelago can be taken as true 

 intermedins, by the shorter and stouter alar spines. 



