G14 



4. Corophium grossipes (Liime). 



(PI. 219). 

 Cancer grossipes, Linn6, Syst. Natune II, p. 1055. 



Syn.: Oniscus volutator, O. Fr. Muller. 

 Astacus linenris, Pennant. 

 Garnmarus longicornis, Fabricius. 

 Corophium longicorne, Latreille. 



Body moderately slender, with the segments of urosome well defined. 

 Cephalon about equalling in length the first 2 segments of mesosome com- 

 bined, rostral projection very slight, lateral lobes small and narrowly rounded 

 at the tip. First pair of coxal plates rather produced in front, and tipped 

 with about 5 strong setse. Eyes very small, but distinct, with dark pigment. 

 Superior antennae in female considerably exceeding YS of the length of the 

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

 much expanded, and longer than the other 2 combined, its outer edge in 

 female being armed with 2 strong spines, in male minutely serrulate, flagellum 

 nearly as long as the peduncle, and composed of 12 14 articulations. Inferior 

 antennae in female much stronger than the superior, and about half the length 

 of the body, penultimate joint of the peduncle produced near the end below 

 to a short dentiform projection defined above by a deep sinus, last peduncular 

 joint nearly as long as the penultimate one, and quite unarmed, flagellum shorter 

 than that joint ; inferior antennae in male much larger than in female, equalling 

 in length, when fully extended, the whole body, otherwise of much the same 

 structure as in the latter. Anterior gnathopoda with the propodos a little 

 shorter than the carpus, and but very slightly widening distally, palm nearly 

 transverse. Posterior gnathopoda with the propodos about the length of the 

 carpus and meral joint combined, dactylus rather elongated, and perfectly 

 smooth. Anterior pairs of pereiopoda with the meral joint moderately ex- 

 panded and shorter than the last 2 joints combined, dactylus scarcely longer 

 than the propodal joint. Penultimate pair with the meral joint fringed on 

 both edges with numerous ciliated setse. Last pair moderately elongated, 

 with the basal joint rather expanded and oval in form. Last pair of uropoda 

 with the basal joint somewhat broader than the terminal one, the latter 

 rounded oval in form and rather densely setous. Telson subtriangular, 

 tapering to an obtuse point. Body whitish, variegated along the back and 

 on the inferior antennae with a dark brown pigment. Length of adult female 

 6 mm., of male about the same. 



