104 MR. G. 8S. BRADY ON SPECIES OF 
XI.—On Species of Ostracoda new to Britain.* By Guoran 8. 
Brapy. 
[Plates II. & III.] 
Tue following species of freshwater Entomostraca have been 
taken during the present year (1863) in the counties of North- 
umberland and Durham. One of them (Cypris affinis) is a 
Continental species, not heretofore recorded as a native of Bri- 
tain. The rest are now for the first time described. To these 
descriptions I have appended a few notes on the animal of 
Cyprideis torosa (Jones), and on its occurrence in a recent state 
in this district. 
Famity Cypride. 
Supram. 1, CYPRINA, Dana. 
Genus CYPRIS, Miller. 
Cyrris opnonaA, n. sp. (PI. IT, figs. 1-4.) 
Elongate, subreniform; lower margin slightly sinuated; 
upper edge considerably arched, highest in the middle ; 
extremities rounded, the posterior being the more obtuse. 
Seen from above, the carapace is ovoid in shape, the 
junction of the valves forming, towards the extremities, a 
well-marked keel, which is most prominent anteriorly. 
The valves are clothed with a few scattered hairs, and 
marked irregularly with one or more transparent patches, 
which appear light or dark according to the mode of 
illumination. Colour light brown. Length ,¢$, inch; 
height ;26, inch. 
This species is nearly allied to C. fusca, which differs from it 
in being broader and more tumid, as well as in the surface- 
markings. The abdominal rami of the two species are also 
different, as may be best seen by a comparison of the figures 
(PI. IL., figs. 4 & 5). The “lucid spots” are much larger and 
more distinct in C. oblonga. It is perhaps worthy of notice that 
fa This paper appeared also in the Annals and Magazine of Natural History for January, 
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