266 Miss H. Richardson on the Isopods of the 



Flah. Awaatscli Bay, Sea of Ochotsk ; north-west coast of 

 North America to Vancouver Island {Miers). 



43. Idotea stenops, Benedict. 



Idotea stenops, Benedict, Proc. Biol. Soc. Washington, xii. 1898, 

 pp. 54, 55. 



Hah. Monterey, California. 



44. Idotea Whitei, Stimpson. 



Idotea Whiter, Stimpson, Proc. Acad. Nat. Sci. Philad. 1864, p. 155 ; 

 Miers, Journ. Linn. Soc. London, Zool. xvi. 1883, pp. 42, 43. 



Tlab. Paget Sound; Monterey Bay, California, collected 

 by Mr. Heath. 



A specimen from Monterey Bay, California, agrees with 

 Miers's description of two males received from California, 

 which he refers to this species. It is unlike Idotea Wosne- 

 senskii in the following points, and from an examination of a 

 large number of individuals of /. Wosnesenslcii , in which 

 these points remain constant^ it seems to demonstrate the 

 impossibility of uniting the two species : — 



1. " Form of epimera of second to fourth thoracic segments, 

 which reach quite to the postero-lateral angles of these 

 segments. 



2. " Epimera of the second segment are broader anteriorly, 

 and the terminal segment more resembles that of /. ochotensis, 

 being more angulated and less rounded at the postero-lateral 

 angles " *. 



3. The absence of hairs on the legs. 



The legs of /. Wosnesenskii (the males) are thickly covered 

 with hairs and very bushy in appearance. 



4. The smooth margins of the epimera, which in 7. Wosne- 

 senskii have thickened edges. 



19. Synidotea, Harger. 



Analytical Key to the Species o/" Synidotea f. 



a. Abdomen emarginate or notched at its 

 distal end. 

 h. Two spines or tubercles overhanging 

 the frontal notch. 

 c. Spines united near the base 45. S. pallida, Benedict. 



Columbia,' ii. 1866, p. 282) refers, without any description, specimens from 

 Esquimault Harbour, British Columbia, to liioitea s^nc^a^Dana; it is far 

 more probable that they belong to Idotea ochotensis^ 



* Miers, Journ. Linn. Soc. London, Zool. xvi. 1883, pp. 42, 43. 



t Benedict, Proc. Acad. Nat. Sci. Philad. (1897), p. 391. 



