194 



lamellar, with the distal joint generally well defined and the proximal joint ex- 

 panded inside. Only a single ovisac present in female. 



/.'<///"//.-.- To this family I refer a number of genera, which, as regards 

 both the external appearance and the structure of some of the appendages, exhibit a 

 perplexing similarity to the more typical Dn^m-ailr (Ami>h'i<i*<-nx). though differing 

 materially in a tew points. Thus in all the forms only a single ovisac is present 

 in the female, and the rostrum never attains that full development which is charac- 

 teristic of the D'uixiicr'iiln'. being in most cases reduced to a very minute im- 

 mobile point. The outer ramus of the posterior antenna 1 is very small, and this 

 is also generally the case with the nuvndibular palp. As to the legs, the 1st pair 

 are often built upon a very similar type to that in the Dio*ttrritln'. the inner ramus 

 being generally longer than the outer, and more or less prehensile. On the other 

 hand, this ramus, in the natatory legs, is as a rule less fully developed than in 

 the f)i<j*<in-i<l,r. The present family is represented both in fresh water and in 

 the sea, some forms also in brackish water. 



Gen. 4'2. CanthOCamptllS, Westwood, 1N3(). 



Syn: Canthocarpus. Haird. 



Generic Character*. Body slender, eylindric in shape, and very flexible, 

 with the anterior division only little broader than the posterior. Cephalic segment 

 of moderate size and not very deep; rostral projection very small, and rudiment- 

 ary. Epimeral plates of the 3 succeeding segments comparatively small and 

 rounded behind ; last pedigerous segment scarcely narrower than the preceding 

 me, but without true epimeral plates. Urosome well developed, with the segments 

 -pinulose at tin- hind edge ventrally and laterally, genital segment in female large 

 and imperfectly divided in the middle, last segment short, with a distinct anal 

 opercle edged with regular spimilus. Caudal rami slightly produced and provided 

 outside with 2 hair-like bristles, apical seta' normal. Kye well developed. An- 

 terior antenna' more or less slender, 8-articiilate. tlm>e in male strongly hinged. 

 l'i!eriur anteniKi- with the outer ramus rather small. Inarticulate, distal joint the 

 -mailer. Oral parts on the whole poorly developed. Mandihiilar palp simple, 

 Inarticulate. .Maxilla' without distinctly defined exopodal and epipodal plates. 

 Anterior maxillipeds pro\ided with only "2 digitiform lobules inside the unguiferous 

 joint. Posterior maxillipeds normally de\e] ( .prd. 1st pair of legs with the inner 



