58 



Gen. 1. JEgSL, Leach, 1815. 



Generic Characters. — Body rather compact, with very hard integuments, 

 and the segments of mesosome nearly equal in size, the 4 posterior ones 

 generally having a line running across them dorsally. Coxal plates thick, sculp- 

 tured outside with 2 curved ridges, and produced posteriorly to an acute point. 

 Metasome not much narrower than the mesosome, its 5 anterior segments very 

 short, and having the epimera acutely produced. Eyes large, reniform, sometimes 

 approaching dorsally, so as to meet in the middle. Superior antennas rather short, 

 with the first 2 peduncular joints more or less expanded. Anterior lip having in front 

 a smooth linguiform plate (epistome) projecting between the bases of the inferior 

 antenna?. Posterior lip terminating in 2 comparatively small, lanceolate lappets. 

 Mandibles having at the base outside a well-developed 3-articulate palp, inner 

 part of the body greatly produced, and terminating in a sharpened, knife-shaped 

 cutting edge, molar expansion wanting. Anterior maxilla with only a single 

 narrrow masticatory lobe tipped by short spines. Posterior maxilla broader, sub- 

 lamellar, terminating in 2 unequal lobes artned with recurved denticles. Maxilli- 

 peds rather strong, epignath confluent with the basal part, masticatory lobe rudi- 

 mentary, terminal part (palp) 5-articulate, incurved, subtortuous, and armed with 

 strong recurved denticles. Anterior pairs of legs with the propodos simple cylind- 

 ric, not expanded, dactylus abruptly curved in the middle, and terminating in a 

 very acute point ; the 4 posterior j>airs successively increasing in length, with the 

 propodal joint short, and the dactylus comparatively small. Uropoda with the 

 basal part produced at the inner corner to a narrow lanceolate process. 



Remarks. — This genus was established as early as in the year 1815 by 

 Leach, and represents the type of the family JEgvlce. It is chiefly distinguished 

 from the other 3 genera represented in the Norwegian fauna, by the compara- 

 tively broad metasome, the large reniform eyes, the structure of the antenna and 

 that of the mandibles and maxillipeds. Moreover, some differences are found in 

 the structure of the legs. The iEga comprise some of the largest known Iso- 

 poda, and are well known by our fisher-men by their frequent occurrence on the 

 skin of fishes of various kinds. They are generally named here in Norway 

 "Fisk-Bjorn", that is, fish-bear. The genus comprises rather a large number of 

 species from different parts of the Oceans, amounting to more than 20 in all. 

 To the fauna of Norway belong 7 specie's, to be described below. 



