524 



22. Cheirocratus Sundewalli, (Rathke). 



(PL 184. PI. 185, fig. 1). 



Gammarus Sundeivalli, Eathke, Acta Acad. Leop. Vol. XX. p. 65, PI. Ill, fig. 2. 



Syn: Lilljeborgia shetlandica, Sp. Bate 5. 



<i Protomedeia Whitei, Sp. Bate Q. 



» Lilljeborgia Normani, Stebbiug. 



« Clieirociatus brevicornis, Hoek. 



Body moderately slender and rather compressed, witli tlie back 

 evenly rounded. First segment of urosome produced dorsall^^ to 3, 2nd to 4 

 juxtaposed dentiform projections, having between them stiff bristles; last 

 segment without denticles, but with two bristles. Cephalon about the length 

 of the iii'st 2 segments of mesosome combined, lateral parts, as it were, bifid 

 in front, exhibiting above, a narrow rounded lobe (the lateral corners), and 

 below, a triangularly produced projection (the postantennal corners), both 

 partly obtecting the base of the inferior antennae, and separated by a narrow 

 incision. Anterior pairs of coxal plates scarcely as deep as the corresponding 

 segments, 1st pair somewhat expanded distally, and angularly produced in 

 front; 2nd pair evenly rounded at the tip, and considerably deeper in male 

 than in female; the 2 succeeding pairs subquandrangular in shape, and succes- 

 sivel}' diminishing in depth; 5th pair fully as deep as the preceding pair, 

 and having the anterior lobe the larger. Last pair of epimeral plates of 

 metasome produced at the lateral corners to an acuminate projection. Eyes 

 rounded, with reddish brown pigment. Superior antennae scarcely attaining 

 Vs of the length of the body, and much shorter than the peduncle of the 

 inferior ones, 1st joint of the peduncle about the length of the 2nd, but much 

 thicker, and having at the end posteriorly 2 slender spines and several 

 delicate bristles, 3rd joint comparatively small, scarcely exceeding in length 

 Vs of the 2nd, flagellum about the length of the peduncle, and composed of 

 from 16 to 18 articulations, accessory appendage extremely small and biarticulate. 

 Inferior antennae nearly twice as long as the superior, last joint of the 

 peduncle much longer than the penultimate one, flagellum shorter than those 

 joints combined. Anterior gnathopoda of same structure in both sexes, carpus 

 rather elongated, and densely setiferous below, propodos somewhat shorter 

 than the carpus, and much narrower, gradually tapering distally, and densely 

 setiferous on both edges, dactylus very small, and denticulated inside. 

 Posterior gnathopoda in female very like the anterior, though a little more 

 slender, and having the propodos about the length of the carpus; those in 



