404 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 115 



Gnatliopocl 1 with fifth joint longer than sixth, which is distinctly 

 subchelate. Sixth joint with palm obhque, convex, defined by spines, 

 and about as long as hind margin of joint. Seventh joint fitting 

 palm and armed on inner margin with minute spinules. Gnathopod 

 2 large (fig. 6c); palm very oblique, defined by stout sharp tooth, 

 with large tooth in middle, on either side of which are small teeth; 

 seventh joint strong, fitting palm. Pereopods 1 and 2 slender, 1 

 slightly slenderer than 2; fourth joint not produced downward in 

 front; seventh joint rather long, slender, shghtly curved. Pereopods 

 4 and 5 with second joint expanded; fourth joint very slightly ex- 

 panded, only slightly produced downward; seventh joint about % 

 length of sixth. Pleon segment 3 about as shown by Sars (1895, 

 pi. 94, fig. 2) for Metopa invalida. Uropod 1 reaches back slightly 

 farther than uropod 2, 2 slightly farther back than 3. Uropod 3, 

 peduncle slightly shorter than ramus, first joint of which is shorter 

 than second (fig. 6/0- Telson narrowly oval with narrow rounding 

 apex, and bearing 3 short spines on either lateral margin. Length 

 6 mm. 



Female. — Gnathopod 2 not as large as in male; palm oblique, 

 convex, defined by tooth and 2 spines (fig. 5e), and armed throughout 

 with small rounding teeth, one of which near middle is shghtly larger 

 than rest; seventh joint fitting palm. 



Remarks. — The above description is based on the 2 syntypes, 

 a male and a female, USNM 38550, from Albatross station 4516, 

 Monterey Bay, California, May 24, 1904, 718-756 fathoms, among 

 hydroids on the back of a spider crab, Hyas species. 



Holmes' species is here placed in the genus Proboloides Delia Valle, as 

 it differs from Metopa by having a 2-jointed palp to maxilla 1 and not a 

 1 -jointed palp as in Metopa. It was assigned to Metopella Sars by 

 Gurjanova (1951), perhaps on the basis of Holmes' statement (1908): 

 "Last three peraeopods with the merus not widely expanded" — but, 

 as shown herein, the merus is widely expanded on pereopods 4 and 5. 



Family Tironidae 



Syrrhoe longifrons, new species 



FiGUBE 7 



This species differs from S. crenulata Goes (1866) as follows: Head 

 elongate, about as long as first 5 body segments combined, produced 

 slightly forward, evenly rounding. Rostrum pointing downward and 

 backward toward body, not straight downward as in S. crenulata. 

 Eyes reddish brown in alcohol, elongate, about )i as long as head, 

 united above and occupying almost entire front of head. Lateral 

 angle of head truncate, not angular. Lower front corner of fkst 3 



