NO. 1175. ISOPODS OF THE PACIFIC COAST— RICH AEDSON. 82' 



is about twice as wide as the outer branch; is obliquely truncate, and 

 crenulate. Theouter branch is narrow, rounded posteriorly, and smooth. 

 Both branches are fringed with hairs. 



The legs are long and slender. Five spines are present on the merus 

 of the prehensile legs. The gressorial legs are but slightly spinulose. 



Two specimens examined were collected at Monterey Bay, California, 

 by Mr. Heath. 



The description of this species of u^ga by Dana as u^gacylla lecontii 

 was from a young specimen.' The individual sent us is thought to be 

 the adult form, and differs from Dana's description^ of the young indi- 

 vidual in the crenulated posterior margin of the terminal segments, in 

 the truncated inner branch of the uropoda, and in the addition of two 

 joints to the length of the flagellum of the second pair of antennae. 



7. ROCINELA Leach. 



ANALYTICAL KEY TO SPECIES OF HOCINELA. 



a. Flagellum of second pair of antenna' with fourteen to sixteen joints. 

 b. Propodus of prehensile legs with two io four spines, 

 c. First thoracic segment with antero-lateral angles produced hornlike at sides 

 of head. Frontal margin of head produced. 8i)ot8 wanting on fourth and 

 fifth abdominal segments and base of terminal segment. 



10. liooinela cornuia Kicbardson. 



c'. First thoracic segment normal. Frontal margin of head not produced. 



Spots present on fourth and fifth abdominal segments and base of terminal 



segment 11. Hoeiiiela belliceps (Stimpson). 



h' . Propodus of prehensile legs with five or six spines. 



12. Rocinela laticauda Hansen. 

 a'. Flagellum of second pair of antenna': with ten to eleven joints. 

 b. Tubercles developed on all the segments of the body. 



l.S. liocincla tuberculosa Richardson. 

 b' , No tubercles developed on body. Teruiinal segment of body ornamented with 

 a very wide crescentiform band, from whose posterior border three large 

 hastiform stripes project backwards. 



14. Bocitiehi aries Schicedte and Meinert. 



IO. ROCINELA CORNUTA Richardson. 

 Rocinela cornuia Riciiardsox, Proc. Am. Phil. Soc, XXXVII, 1898, p. 12, figs. 1, 2. 

 Habitat. — Off Shumagin Bank, Alaska. 



II. ROCINELA BELLICEPS (Stimpson). 



JEga belliceps Stimpson, Proc. Acad. Nat. Sci. Phila.; XVI, 1864, p. 155. 

 JEga alaskensis Lockington, Proc. Cal. Acad. Sci., VII, 1877, Pt. 1, p. 46. 

 Rocinela alascensis Richardson, Proc. Am. Phil. Soc, XXXVII, 1898, p. 11. 



' Schinjdte and Meinert regard Jigacijlla Dana as synonymous with JFga, and 

 remark that Dana's specimen, by which the genus ^Egacylla was instituted was a 

 young Aiga. See Naturhistorisk Tidsskrift, XII, 1879-80, p. 334. See also Liitken, 

 Vid. Medd. Naturh. For., I'-fiO, p. 180. 



^ There are no specimens of the young in the National Museum. 



