44 ME. E. J. MIEES ON THE IDOTEID^. 



p. 26 (1851) ] Kinahan, Nat. Hist. Rev., Pr. of Soc. vi. p. 84 (1859) ; 



S. Bate ^' Westw. Brit. Sessile-eyed Cr. ii. p. 386, fig. (1868) ; Brady 



8f Robertson, Ann. cf- Mag. Nat. Hist. (ser. 4) iii. p. 361 ; Parfitt, Rep. 



Devon Assoc, vi. p. 255 (1873); Metzyer, Jahresb. der Commiss. z. 



wiss. Untersuch. des deutschen Meeres, p. 285 (1875); Meinert, Nat. 



Tidsskr. (3 R.) xi. p. 82 (1877), xii. p. 470 (1880); Sm, List Cr. 



Aberdeen, p. 11. 

 ? Idotea excisa, Bose, Hist. Nat. des Crust, ii. p. 181 (1802). 

 ? Idotea marina, Latr. Hist. Nat. Cr. vi. p. 367, vii. pi. Iviii. fig. 5 



(1803-4) ; Lam. Hist. Anim. sans Vert. v. p. 160 (1818), 7iec Linn. 

 Idotea oestrum, LeacA, Linn. Trans, xi. p. 365 (1815); Desm. Consid. 



Cr. p. 289 (1825). 



The body is convex, oblong-oval, nearly smooth. Head vrith 

 the anterior margin nearly straight, almost imperceptibly concave, 

 its antero-lateral angles not at all prominent ; segments of the 

 thorax of nearly equal length in the middle line of the back, the 

 first segment with rounded or subacute antero-lateral lobes that 

 reacli to or nearly to the eyes ; postabdomen longer than the four 

 posterior thoracic segments, terminal segment convex above, with 

 the lateral margins nearly straight and slightly convergent poste- 

 riorly to the distal extremity, which has a rather broad and shallow 

 eraargination ; the postero-lateral angles of the terminal segment 

 are rounded or subacute, never acute. Eyes small, black. An- 

 tennules usually not reaching to the distal end of the penultimate 

 joint of the peduncle of the antennae, with their basal joints 

 moderately dilated. Antennae of moderate length, usually not 

 reaching, when retracted, to the posterior margin of the fourth 

 thoracic segment ; the terminal joint of the peduncle but little 

 longer than the preceding ; the flagellum 12-20-jointed. Epimera 

 large and broadly developed ; those of the three or four posterior 

 segments with the postero-lateral angles subacute. Opercular 

 valves with the terminal plates nearly square, their distal ends 

 slightly emarginated. The colour in dried or spirit-specimens is 

 a more or less yellowish brown, the surface of the body being 

 covered with minute dots which are not always visible. The 

 largest specimen I have seen measures nearly ly^ inch (35 

 miilim.) in length, and its greatest breadth is nearly ^ inch 

 (11 miilim.); but adult examples are usiially smaller. 



This species probably occurs, but (it would seem) locally, 

 throughout the warmer and temperate seas of Europe. It 

 has been recorded from the Mediterranean, British, Danish, and 

 Southern Scandinavian coasts, Heligoland, &c. 



