28 



Anteiiiine somwliat more rolrast, but otherwise rather similar. Gnathopoda of 

 female having the propodos comparatively larger, much longer than the 2 

 preceding joints combined, oblong oval in form, witli the palm very oblique 

 and less distinctly defined below; 2nd pair in male with the propodos oldong 

 in form, distinctly tapering toward tlie tip. Pereiopoda very robust, edged 

 witli scattered small spines, propodal joint, especially of the 3 posterior ])airs, 

 considerably dilated and armed on the anterior edge below the middle with 

 2 unusually strong serrated spines, dactylus very powerful, falciform cun'ate. 

 Ccdour yellowish. Length of female 7 mm. 



licmarlcs. — Tliis is evidently a well marked species, differing very 

 deciiledly froni the typical form by the peculiar imln-icated appearance of the 

 liody-segments and espeeiaUy by the rather different structure of the legs. 

 Tlie colour also is rather dissimilar. 



OcviinriHT. — I have myself only met with a single female s})ecimen 

 of this species, which was taken on the west coast of Norway. In our Uni 

 versify Museum are, however, 2 specimens, male and female, collected by 

 Boeck, the one on the shores of Kanno, the other at Farsund (south coast of 

 Noi'way). According to the Rev. Mr. Stebbing, this species is far less active 

 than }{. Nilssoni, quite wanting the jjower of leaping, when out of water. 



Bistrihiition. — British Islands, France, coast of Algiers (Chevreux). 



Fam. 2. Lysianassidae. 



Body generally rather high, more or less compressed, glabrous, with 

 the back evenly vaulted. Coxal plates deeji, 4th pair generally the largest 

 and deeply emarginated posteriorly to receive the rounded 5th pair. Meta- 

 some well developed, with large e])inicral [)lates. Urosome short and thick, 

 more or less convex above. Superior antenna^ furnished with an accessory 

 appendage, peduncle short and thick, tiagellum more or less elongated, with 

 the 1st joint generally i-ather large ond beset with dense tufts of sensitive 

 hail's. Inferior antennae more slender than the superior and having the basal 

 joints not coalesced with the cephalon, tiagellum in male often greatly elongated 

 and Hliform. Epistome generally projecting in front of the anterior lip; the 

 latter more or less produced anteriorly. Mandibles less strong than in 

 the Orchestiidse, cutting edge sinijile. not denticulated, molar expan- 

 sion rather small or i[uitp wanting, ))al]i large, triarticulate; between 

 the latter and the cutting edge a more or less distinct rounded ac- 

 cessory bibc. First ]iair nf niaxillic witli t1ic Jial]! generally well devel- 



