15 PEOCEEDIFGS OF THE NATIOISTAL, MUSEUM vol.77 



of jjedimcle together and composed of about seven joints. Epistome 

 linguiform, projecting very prominently beyond the upper lip. Man- 

 dible about as shown by Sars for O. hatei ^ Maxilla 1, outer plate 

 with 11 serrate spine-teeth. Maxilla 2, outer plate broader than 

 inner. Maxilliped, inner plate reaching to end of first joint of palp 

 and bearing three apical teeth, outer plate broad, reaching end of 

 second joint of palp, armed on upper inner edge with a row of low 

 flat teeth and on the under surface with four short spines and on 

 the inner edge with two longer spines. Lower lip about normal, but 

 outer edges somewhat constricted. Gnathopod 1, fifth joint shorter 

 than sixth, lower margin produced into a narrow forward pointing 

 lobe, sixth joint narrowing distally and about twice as long as its 

 greatest width, palm slightly convex, crenulate, and defined by two 

 stout spines, one on the outer and the other on the inner surface of 

 the joint, dactyl slightly overlapping palm, bearing a single tooth 

 on inner edge and several setae near apex. Gnathopod 2, fifth joint 

 nearly twice as long as sixth, under broadly lobed surface bearing 

 many short forward-pointing spinules or scales, sixth joint twice as 

 long as wide, minutely produced, but not so strongly as is shown by 

 Sars for 0. hatei. Peraeopods 1 and 2 normal. Peraeopod 3, sec- 

 ond and fourth joints greatly expanded. Peraeopod 4 possibly 

 slightly longer than 5, second joint not so much expanded as in 

 peraeopod 3, fourth joint less expanded than in 3, but slightly more 

 than in 5. Peraeopod 5 second joint more expanded than in 4. Pleon 

 segment 3 with lower portion of postero-lateral margin bearing about 

 four coarse teeth, second pleon segment bearing a few much shallower 

 teeth. Pleon segment 4 bearing rounding dorsal process. Uropod 1 

 projecting backward slightly farther than 2 or 3, which project 

 equally. Telson cleft about one-third of its length with lobes gaping. 



Length. — Largest specimens measure about 8 mm. 



Type.— Cdit. N"o. 35774, U. S. N. M., Bay of Fundy, taken by the 

 U. S. Fish Commission in 1872. Original number 552. 



Other specimens in the Museum collection are as follows: 



Bay of Fundy, U. S. Fish Commission, 1872. Original number 

 309, 3 specimens ; original number 321, 4 specimens ; original number 

 407, 4 specimens ; original number 410, 1 specimen ; original number 

 454, 8 specimens; original number 552, 2 specimens (Paratypes) ; 

 no original number, 13 specimens. 



All the specimens were taken by the U. S. Fish Commission in 

 1872 in the Bay of Fundy, in the vicinity of Grand Manan. 



This species appears to be most closely related to O. tschernyscJieri 

 Briiggen from Jugor Strait, but in the present species the lobe of 



2 Sars, Crustacea of Norway, vol. 1, pi. 22, flg. ni. 



