Pacific Coast of North America. 263 



36. Olyptonotus Sahini (Kroyer). 



Idotea Sabini, Kroyel', Nat. Tidsskrift, 2nd ser. ii. 1847, p. 401 ; Atlas 

 of Crust, in Gaimard's Voy. en Scand. pi. xxvii. fig. 1 ; Reinhardt, 

 P'ortegnelse over Gronland's Krebsdyr, 1857, p. 34; Liitken, List of 

 Crust, of Greenland in Arctic Manual, 1875, p. 149; Sars, Arch. f. 

 Math, og ISTaturvidensk. ii. 1877, p. 350. 



Chiridothea megalura, G. 0. Sars, Archiv f. Math, og Naturvidensk. 

 iv. 1880, p. 432. 



Glyptonotus Sabini, Miers, Journ. Linn. Soc. London, Zool. xvi. 1883, 

 pp. 15, 16, pi. i. figs. 3-5. (See Miers for further synonymy.) 



Hah. Circumpolar ; west coast of North America [Miers). 



18. Idotea, Fabricius. 



Analytical Key to the Species of Idotea *. 



Terminal segment emarginate at its extre- 

 mity 37. I. resecata, Stimpson. 



'. Terminal segment not emarginate at its 



extremity. 

 b. Body slender, linear, filiform. 



c. Terminal segment truncate at apex . . 38. /. graeillitna, Dana. 

 c'. Terminal segment acute at its extre- 

 mity. 

 d. Postero-lateral angles of terminal 

 segment prominent and separated 

 by a tooth from subtriangular 

 middle portion, which bears a small 



tooth at the middle 39. I. urotoma, Stimpson, 



d'. Postero-lateral angles not separated 



by a tooth from middle portion . . 40. /, rectilineata, Lock- 

 h' . Body oblong-ovate. [ington, 



c. Terminal segment regularly rounded, 



■with small median point 41. /. Wosmsenskii, 



c'. Terminal segment triangulate poste- [Brandt, 

 riorly, with subparallel sides. 

 d, Epimera of second, third, and fourth 

 segments short, not reaching the 

 post-lateral angles of their respec- 

 tive segments 42. /. ochotensis, BraJidt. 



d'. Epimera of all the segments reaching 

 the post-lateral angles of their re- 

 spective segments. 



e. Sides of thorax arcuate 43. /. stenops, Benedict. 



e'. Sides of thorax more nearly 



parallel 44. 1. Whitei, Stimpson. 



37. Idotea resecata, Stimpson. 



Idotea resecata, Stimpson, Bost. Journ. Nat. Hist. vi. 1857, p. 64, 

 pi. xxii. tig. 7 ; Proc. Bost. Soc. Nat. Hist. 1859, p. 88 ; Miers, 

 Journ. Linn. Soc. London, Zool. xvi. 1883, p. 45. 



♦ See Miers, Journ. Liim. Soc. London, Zi;ol. xvi. 1883, p. 43. 



