564 



13. Megamphopus cornutus, Norman. 



(PI. 200). 



Megamphopus cornutus, Norman, Last Report on Dredging among the Shetland Isles: Report 

 of the Brit. Assoc. f. the Advanc. of Science, p. 282, 



Syn: Protomedeia longimana, Boeck. 



Body rather slender, though scarcely compressed, being somewhat 



tumid in the female. Cephalon exceeding in length the first 2 segments of 



mesosome combined, frontal part very much produced, lateral corners acut- 



angular, postantennal ones far behind the latter. Anterior pairs of coxal 



plates in female about as deep as the corresponding segments, and rounded 



quadrangular in form; 5th pair with the anterior lobe nearly as deep as the 



preceding pair, and evenly rounded. Coxal plates in male somewhat differing 



from those in female; 1st pair produced in front to an acuminate projection, 



which is sometimes deflexed in the form of a horn; 2nd pair much larger 



than any of the others; the 2 succeeding pairs successively diminishing in 



size. Last pair of epimeral plates of metasome obtusely rounded at the 



lateral corners. Eyes rather large, oval in form, and placed on each side 



of the frontal part of the cephalon, pigment dark brown. Superior antennae 



not nearly attaining half the length of the body, 1st joint of the peduncle 



comparatively short and thick, being about half as long as the cephalon, 2nd 



joint considerably longer and much narrower, 3rd joint about the length of 



the 1st, flagellum scarcely longer than the peduncle, and composed of about 



8 articulations, accessory appendage extremely small and uniarticulate. 



Inferior antennae somewhat longer than the superior, with the flagellum 



exceeding half the length of the peduncle. Both pairs of antennas provided 



along their posterior edge with tufts of slender bristles. Anterior gnathopoda 



in female rather feeble, with the propodos about the length of the carpus, 



and slightly dilated in the middle, being oblong sub fusiform in outline, 



dactylus rather slender. Posterior gnathopoda but little larger than the 



anterior, propodos oblong in form, and gradually tapering distally, without 



any distinct palm. Both pairs of gnathopoda in male much larger than in 



female, and rather elongated ; the anterior ones having the carpus nearly as 



long as the basal joint, and provided below with several fascicles of bristles, 



and anteriorly with an obtuse dentiform projection, propodos shorter than 



the carpus, and oblong oval in form, lower edge armed with a series of 



