g40 GAMMAR1D.E. 



AMPHIPODA. GAMMARIDES. 



NATATORIA 



DEXAMINE TENUICORNIS. 



Specific character. First joint of the peduncle of the superior antennaj 

 without a tooth at its extremity. 



Length 4 lines, Rathlie ; Brit. Spec, -jg inch. 



Dexaminc tenuicornis. Rathke, Beitr. zur Fauna Norwegens, Nov. Act 

 XX. p. 77, pi. xliv. fig. 3, 1843. Liljeborg in 

 Ofvers. af Kongl. Vet. Akad. Forhandl. p. 22, 

 1851. 



The head of this animal, according to Rathke, is not 

 produced to a rostrum. The eyes are oblong. The su- 

 perior antennae have the first joint of the peduncle short 

 and tolerably stout, but the second is two or three times 

 longer than the first ; and the flagellum is very long and 

 slender. The inferior antennae have the penultimate 

 joint of the peduncle very short, and the ultimate quite 

 as long as that of the superior pair. The last pair of 

 walking legs have the posterior margin of the thighs 

 slightly crenulated, and the fingers of all the legs are pro- 

 portionally much longer than in D. spmosa, to which 

 species, in all other respects, this animal closely approxi- 

 mates. Like Montagu and Milne-Edwards, Rathke drew 

 his figure from an animal (taken at Drontheim, on the 

 coast of Norway) which had lost the middle tail-piece ; 



