50 G 



PllOCKEDISGS OF THE NATIONAL MUSEUM. 



VOL. XXVIII. 



It carries on its outer iiKii"<iiii thivo claws of about the same lenotii, 

 at the outer |)()sterior corner a h)n<»- plumose seta or a spine lonocT 

 than the claws, and on its posterior border three stout plumose seta\ 

 Occasionally one of the terminal claws is developed at the expense of 

 the others, as in Lepeoplifhc'n'tix iiKDidccoitlmK and L. qinidrctiis and 

 CalujodeH )iic(incephidA<><- 



In the oenus (rloiojxjU.s two of the claws are curiously modified into 

 a three-proiiued fork. 



One or two speci(\s have been reported in which there were no 

 plumose sette upon the posterior ])order (<■ W//V/^/.v Inrinuhmis and ('. 

 j>/'o(ia('fi/s). 



The endopod of these tirst legs is rudimentary and is represented in 

 some species by a minute joint bearing setiB {L(pcoj>/ithetni,s i)ectorali>^) 

 and in others simply by the seta? ( Caln/us rapiix and 0. honito). 



In the second pair of legs both exopod and endopod are well devel- 

 oped, two- or three-jointed, and plentifully' supplied with plumose seta?. 



Fig. 13.— First swimming i.ec; of .mu'lt female Caligus bOiVITo, ventral view. 



These latter point inward on either leg and are often long enough to 

 overlap on the mid line, thus fonning a very effective swimming lam- 

 ina. These legs are ahuost exactly alike in all the genera. The large 

 basipod carries on its posterior margin a stout plumose seta, inclined 

 backward and inward at an angle of about 4;y^. The basal joint of the 

 exopod is longer than either of the other two joints and carries a plu- 

 mose seta on its inner margin and a stout spine at the outer distal cor- 

 ner (tig. 1-i). The second joint is short, with a plumose seta on the 

 inner margin and a spine at the outer distal corner. The terminal 

 joint is almost circular in outline and carries a row of six plumose sette 

 around its edge and a spine at the outer corner. 



This exopod is in nearh' the same line as the basipod, but the endo- 

 pod is ])ent inward until in Cab'git.-i and Lcpeopldheiru^i it is at right 

 angles to the >)asipod, w^hile in Glolopotes and AJehhw it is nearly par- 

 allel with it, l)ut running in the opposite direction. The basal joint of 

 this endopod is short and carries a single i)lumose seta on its inner 

 margin. The second joint is the longest of the three and usuall}' the 

 widi^st, and c:irries two })lumo.se .seta3 at its distal end. The circular 



