172 University of California Publications. | ZooLocy 
rical. Anterior antennae 24-jointed; joints 24 and 25 fused. 
Outer ramus of posterior antennae 7-jointed and almost 1144 
times as long as the inner ramus. The distal bristles of the ante- 
rior maxillipeds sickle-shaped, with spinous feathering, and much 
longer and thicker than the proximal bristles. First basal of the 
posterior maxillipeds with strongly protruding lobes, both the 
middle ones set with bristles, which have a spinous feathering; 
inner ramus well developed, 5-jointed. Rami of swimming feet 
usually 3-jointed, but the inner ramus is exceptionally 2-jointed. 
First basal with bristle on inner border in first to fourth feet, 
second basal thus equipped in the first pair. First basal of fifth 
pair without inner marginal bristle; inner marginal bristle of 
second joint of outer ramus thorn-like and fused with the joint 
(fig. 32c.) 
4 Sexual peculiarities in the form of the abdomen, right 
anterior antenna, and fifth pair of feet. The abdomen is com- 
posed of five segments; anal segment in most species very short ; 
genital opening on the left. Right anterior antenna a grasping 
organ. Joints 19-21 and 22-23 fused, geniculation between the 
18th and 19th. Inner marginal bristles lacking on outer ramus 
of left fifth foot, joints 2 and 3 fused. The outer ramus of the 
right foot 3-jointed, both distal joints metamorphosed into a for- 
ceps, one blade of which is the terminal joint, while the other is 
the thickened inner marginal bristle of the second joint. 
1. Centropages bradyi Wheeler. 
Centropages violaceus Brady, 1883, p. 83, pl. 37, figs. 1-14. 
Centropages bradyi Wheeler, 1899, p. 174, fig. 12. 
2 Second joint of outer ramus of fifth foot with a stout 
smooth spine (fig. 32c). Sides of inflated genital segment with- 
out spines or knob-shaped projections. Furea symmetrical, with 
a peculiar short, truneated, peg-shaped projection (fig. 320) 
between insertions of the two outer bristles. (Wheeler, 1899). 
4 Joint 17 of right anterior antenna with smooth anterior 
border, not serrate; joints 19 and 20 fused, separated from joint 
21; joint 18 with accessory series of teeth on lower surface 
(Wheeler, 1899). 
