GAMMARIDEA. 



rior much the longer. The head is triangular in an upper view, and 

 pointed rostrate in front. The segments in the species described are 

 more or less nodose or spinous. 



Family CHELURID^E. 



The genus Ghelura of Philippi,* the only one of this family yet 

 discovered, includes a boring species of Amphipod. The body, as 

 described and figured, is nearly cylindrical ; the epimerals of moderate 

 size. The fourth and fifth segments of the abdomen are united, and 

 form a long, styliform joint. The pairs of caudal stylets are very 

 unlike one another, the last being very long and lanceolate ; the pre- 

 ceding short and broad foliaceous; the first pair short styliform. 

 The mandibles are palpigerous. - The antennae are short ; the superior 

 are the shorter and appendiculate ; the inferior are pediform and 

 without a flagellum. 



Family COROPHID^E. 



The Corophidae are near the Gammaridse in the general form of the 

 thoracic legs, and in both sets of abdominal appendages, although 

 usually very dissimilar in appearance when observed in motion. The 

 more common species have pediform or subpediform antennae ; these 

 form the subfamily Corophinjb (Podoceridae, of Leach). There are 

 others — Icilin^e — which have slender flagella, as in the Gammari, with 

 no pediform character. A few — Clydonik^e — have the caudal stylets 

 simple, the legs long and slender, and two long, stout, rigid antennae. 



* Archiv fur Nat., 1839 ; G. J. AUman, Ann. and Mag. Nat. Hist., xix. 361, June, 

 1847. 



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