606 



Fam. 23. Corophiidae. 



Body smooth, depressed, with the metasome and urosome comparatively 

 poorly developed. Coxal plates very small and non-contiguous. Cephalon broad 

 and more or less produced in front, with the lateral lobes small and narrow. 

 Ej^es, when present, placed within the lateral lobes of the cephalon. Antennae 

 more or less slender, the inferior ones, as a rule, more strongly built than the 

 superior ; accessory appendage of the latter either present or wanting. Mandi- 

 bular palps now well developed and triarticulate, now comparatively small 

 with a smaller number of joints. Oral parts otherwise normal. Grnathopoda 

 of different structure in the different genera, and generally rather unequally 

 developed. Pereiopoda now short and stout, now very much elongated. Last 

 pair of uropoda small, uniramous. Telson, as a rule, lamellar and entire. 



Remarks. The forms belonging to this family are generally dis- 

 tinguished by their depressed body and the poor development of the posterior 

 divisions, whereby they are conspicuously divergent from the Amphipodous 

 type, and have an appearance somewhat reminding of the Isopoda. The 

 family is, hoAvever, hot very sharply denned from the Podoceridce, the 

 genus Cerapus showing in some points an unmistakable affinity to the genus 

 Erichthonius of the latter family. To the fauna of Norway belong 6 genera, 

 to be treated of below, 



Gen. 1. CerapUS, Say, 1817. 

 Syn.: Siphonoecetes, Sp. Bate (part). 



Body slender, sublinear, with the metasome and urosome very small. 

 Cephalon produced in front to a well-marked rostrum. Anterior pairs of 

 coxal plates exceedingly small, the 3 posterior pairs considerably larger and 

 distinctly bilobed. Eyes distinct, but small. Antennae not very slender, and 

 subequal in length, the superior ones without any accessory appendage, but 

 having the 1st joint of the peduncle more or less greatly expanded; flagella 

 in both pairs very short. Mandibular palps well developed, o-articulate, 

 with the terminal joint fully as large as the 2nd, and edged with long, curved 

 setae. Anterior gnathopoda of similar structure in the two sexes, and distinctly 

 subcheliform. Posterior gnathopoda in female scarcely stronger than the 

 anterior, and not subcheliform ; those in male very powerfully developed, 



