North, American Centropagidce. 247 



middle of the inner margin into a smooth rounded process, 

 and armed at the outer apical angle with a stout straight 

 spine serrate on the inner margin. Third segment ahout 

 twice as long as its greatest width, dilated at the middle of 

 the inner margin and armed here with a few rather long 

 hairs ; outer margin armed with three spines similar to the 

 one on the preceding segment, and at the apex with a long, 

 narrow, slightly curved process, perfectly smooth, and some- 

 what longer than the segment from which it springs. 



Inner ramus of left fifth leg three-segmented. First seg- 

 ment subquadrate, slightly more than twice as long as wide ; 

 provided at the middle of the inner margin with a hemispher- 

 ical process armed with a few scattered hairs. Second seg- 

 ment somewhat broader than the first and about as long ; 

 armed at the inner proximal angle with a small sharp spine, 

 and at the middle of the inner margin with two irregularly 

 roughened processes provided with hairs ; a long plumose seta 

 on the inner margin just below the lower of the two processes. 

 Third segment slightly narrower and shorter than the second, 

 both margins sulcate, armed with six stout plumose setae 

 arranged about as in the corresponding segment of the inner 

 ramus of the right leg. 



First basal segment of fifth leg of female subquadrate. 

 Second basal segment about as wide as the first and approxi- 

 mately one and three fourths times as long as broad ; hairy 

 at the middle of the inner margin and armed on the outer 

 apical angle with a plumose seta. First segment of outer 

 ramus subquadrate, about one and three fourths times as long 

 as broad ; armed on the inner margin, near the proximal 

 angle, with a smooth hemispherical process, and on the outer 

 apical angle with a stout spine, serrate on the inner margin. 

 Second segment slightly narrower at the base than the first, 

 but widening distally and produced at the inner apical angle 

 into a stout hook-like process armed on the inner margin 

 with six or seven strong teeth, largest near the middle of the 

 hook, and near the proximal end with five or six smaller teeth. 

 On the outer margin of the hook and opposite the smaller 

 teeth of the inner margin are a number of rather minute 



