DACTYLOPUS. 107 
armed above the middle of the inner margin with a 
single, long, plumose seta (fig. 9); middle joint of the 
outer branch thrice as long as the first or third, ciated 
on both margins, the cilia of the outer margin being 
often strong and almost spinous; the second, third, and 
fourth pairs (fig. 11) have the branches nearly equal, 
bearing long plumose sete, and ciliated on the external 
borders ; the inner branch of the second pair in the 
male (fig. 10) has the second and third joints coales- 
cent, the outer margin deeply excavated above and 
below the middle, and bearing one rather large crooked 
spine, several strong short sete, and at the apex two 
stunted spines ; sete of the inner margin three; fifth 
pair (figs. 12 and 15) in the female composed of two 
subequal, broadly ovate joints, each of which bears 
several rather long apical sete; the outer joint has 
also along its free margin a series of oblong, curved, 
pellucid patches (fig. 12 a); in the male the joints of 
the fifth pair are, as is usual in the Harpacticine, more 
angular, smaller, and less profusely setose (figs. 13 and 
16). Caudal segments short; larger tail sete two 
thirds the length of the body, outer sete about half as 
long. Length ~;th of an inch (‘56 mm.). 
This is probably the commonest British species of 
the genus Dactylopus, occurring not unfrequently in all 
kinds of localities, from the brackish water of estuarine 
pools to depths of at least forty fathoms. I have notes 
of itscapture in the following localities: —Durham coast, 
amongst Lamimarie; in brackish pools, at the mouth 
of the Seaton Burn, Northumberland ; dredged off Red 
Cliff and Robin Hood’s Bay, Yorkshire, in thirty-five 
