48 MB. E. J. MIEKS ON THE IDOTEID^. 



Cmier {ed. 3), pi. Ixix. fig. 3 ; Lucas, Anini. artic. in Expl. Set. 



Algerie, Cr. i. p. 61 (1849) ; White, List Cr. Brit. Mus. p. 94 (184?) ; 



id. Cat. Brit. Cr. Brit. Mvs. p. C6 (1850) ; id. Pop. Hist. Brit. Crust. 



p. 224 (1854); Burgersdijk, Annotat. Crust, indigenis, p. 31 (1852); 



S. Bate 8f Wesiwood, Brit. Sessile-eyed Cr. ii. p. 388, fig. (1868) j 



Metzger, Naturh. Gesellsch.zu Hannover, xs. p. 32 (1871) ; Jahresb. 



der Commiss. zu wiss. Untersuch. des deutschen Meeres in Kiel, p. 285 



(1875); Parfitt, Rep. Devon Assoc, p. 255 (1873); Mcintosh, Ann. 



S,- Mag. Nat. Hist. (ser. 4) xiv. p. 274 (1874) ; Marine Invert. St. 



Andrews, Cr. p. 151 (1875); Bos, Bijd. Crust. Hedrioph. Nederl. 



pp. 35, 71 (1874) ; Hoek, Tijd. Nederl. Dierk. Vereenig. (deel 3), 



p. 42 (1876) ; Sim, List Cr. Aberdeen, p. 11. 

 Idotea diodon, Latr. Nouv. Diet. d'Hist. Nat. xvi. p. 105 (1817). 

 Arraida biraarginata, Risso, Hist. Nat. Eur. merid. v. p. 109 (1826). 

 Idotea sexlineata, Krdyer,Nat. Tidsskr. (2 R.)ii. p. 88 (1846); id. Atlas 



of Cr. in Gaimard's Voy. en Scand. pi. xxvi. fig. 1; Meinert,Nat. 



Tidsskr. (3 R.) xi. p. 83 (1877), xii. p. 470 (1880). 

 Oniscus (Idotea) entomon, Balyell, Powers of Creator, Cr. p. 229, 



pi. cxiii. fig. 10 (1851), nee Linn. 

 The body is narrow obloug, almost linear. The head has its 

 anterior margin strongly excavated and its autero -lateral lobes 

 broadly rounded, and is marked with a sinuated impressed line 

 near the posterior margin. The thoracic segments are narrowest 

 at the posterior margins, and the laterally-projecting epimera 

 give a lobed appearance to the sides of the body. The terminal 

 postabdomiual segment is suboblong, but narrowing slightly in 

 its distal portion ; the distal extremity is truncated and triden- 

 tate, the postero-lateral lobes small, but somewhat more prominent 

 than the median tooth. Eyes of moderate size. Antennules 

 with the basal joint not greatly dilated. Antenna in the adult 

 very robust, nearly equalling the body in length, with the last 

 two joints of the peduncle subequal, and each nearly or twice as 

 long as the preceding. The epimera are small, and in the second 

 to fourth thoracic segments appear, in a dorsal view, to occupy 

 the anterior part of the lateral margin, in the fifth and sixth 

 segments its middle part, and. in the last segment its posterior 

 part. The postero-lateral angles of the epimera of the sixth and 

 seventh segments are acute. Each of the legs is armed with a 

 strong and arcuate terminal claw, which is completely reflexible 

 againstthe penultimate joint. The opercular plates present nothing 

 remarkable. The length of the largest male in the collection is 

 about l^inch (38millim.), but average-sized examples do not 

 exceed 1 inch (25 millim.). 



