new and rare British Copepoda. a55 
Body stout, depressed, somewhat like Zaus spinatus in general 
appearance ; rostrum short, truncate. Antennules moderately 
stout, nine-jointed, setiferous and gradually tapering from the 
base; the fifth, seventh, and eighth joints much shorter than 
any of the others. The annexed formula shows the propor- 
tional lengths of the various joints :— 
Proportional lengths of the joints... 14.18.13.11.5. 
5 
4.3.8 
Number of the joints ............ ee paar ie: i So 
Si: 
6 
Secondary branches of the antenne two-jointed, stout, and 
furnished with several plumose sete, the first joint rather 
shorter than the other (Pl. XV. fig. 13). Mandible-palp 
narrow-elongate, sinuate, provided with two small marginal 
and one-jointed branches (Pl. XV. fig. 14). Anterior foot- 
jaws short, dilated, and armed with a strong terminal claw, 
and with three short setiferous marginal processes (Pl. XV. 
fig. 15). Posterior foot-jaws stout, of moderate length, and 
furnished with a strong slightly hooked terminal claw (Pl. XVI. 
fig. 2). First pair of swimming-feet robust; the second 
basal joint is provided interiorly and near the distal end with 
a short hook-like spine; the first joint of the outer branches 
is equal to nearly half the length of the second, while the 
end-joint is very short; the marginal spines of the first and 
second joints are long and slender; the end-joint, which 
bears two small sete on the exterior margin, is armed at the 
apex with two stout claw-like spines, fringed on the outer 
edge with minute hairs, and with an elongate and moderately 
stout seta; a small seta also springs from the distal end of 
the inner margin of the second joint; the first joint of the 
inner branches, which are elongate and fringed with small 
hairs on both margins, bears a moderately long plumose seta 
on the middle of the inner aspect ; the second and third joints 
are very small; each of the inner branches is armed with an 
elongate and powerful terminal claw, fringed with minute 
hairs on the outer edge, and with also a terminal spiniform 
seta; both branches are of nearly the same length (Pl. XVI. 
fig. 3). In the fourth pair, which are comparatively slender, 
the inner branches extend only to about the end of the second 
joint of the outer branches (Pl. XVI. fig. 5). The fifth 
pair are foliaceous; the basal joint, which is broadly subtri- 
angular (its greatest length being equal to only about two thirds 
of the breadth), is provided with five seta—one on the lower 
half of the inner margin and four at the apex ; the two middle 
apical sete: are long and plumose, but all the others are short ; 
the secondary joint is moderately long and subovate, the inner 
25* 
