376 



MR. G. S. BRADY'S MONOGRAPH OF 



narrowest, the hindermost the broadest. On tlie ventral aspect the bands are not visible. 

 The middle and posterior bands are sometimes connected along the hinge-margins by a 

 broad longitudinal band of the same colour (see figs. 27, 28). In this condition it is 

 Cypris sella (Baird). 

 Length in., height y^- in. ,b'*>'v^ 1 ■'^'i»cv>-vw 



C. vidua is a common and widely distributed species. I have specimens from many 

 different localities, ranging from Kent to Dumfriesshire. 



2. Cypridopsis aculeata (LiUjeborg). (Plate XXIV. figs. 16-20, and Plate XXXVI. 

 fig. 10.) 



Cypris aculeata, Lillj. De Crust, ex ord. trib. p. 117, t. xi. figs. 15, 16; Norman, Ann. & Mag. Nat. Hist, 

 vol. ix. (1862) p. 44, pi. ii. figs. 7-10, and Trans. Tynes. Nat. F. C. vol. v. p. 147, pi. iii. figs. 7-10. 



Valves broadly reniform or subtriangular, convex ; greatest height in the middle, equal 

 to two-thirds of the length. The anterior and posterior margins are well rounded, the 

 latter being somewhat the broader of the two. Ventral margin deeply sinuated in the 

 middle ; dorsal very boldly arched, almost angular in the middle. Seen from above, the 

 carapace is ovate, pointed in front, and rounded behind, broadest in the middle ; width 

 equal to half the length. The end view is ovate, rounded at the base and rather pointed 

 above. The whole surface of the shell is thickly pitted and beset with stiff hairs, mingled, 

 more particularly near the dorsum, with strong, pointed spines (fig. 20). Colour bluish 

 green or dirty brown. The limbs are altogether very robust. Setae of the lower antennae 

 about equal, and reaching much beyond the apices of the terminal claws. The mandi- 

 bular palp bears four strongly plumose setae (much like those of Cypris compressa), the 

 uppermost of which is broad and somewhat lancet-shaped. The terminal claw of the 

 first foot is strongly curved, and serrated for a short distance near the apex ; the serra- 

 tures, however, do not extend quite to the point of the claw. 



Length ^ in., height ^ in. - ^ 



Hub. Gravesend, in brackish water {Prof. T. Rupert Jones) ; brackish water in SuflFolk and near Grimsby 

 [Mr. E. C. Davison); Cowpen Marshes, Durham {Rev. A. M. Norman); Monkwearmouth Colliery 

 Pond, Hylton Dene, and Warkworth (G. S. B.). In a pond a little above high-water mark, Cumbrae 

 {Ml-. D. Robertson). 



This pretty species, though apparently much restricted in its range of habitat, occurs 

 very abundantly in congenial situations, preferring, like Cypris salina, water impregnated 

 with saline matters. Of the eight localities here mentioned, seven were slightly brackish 

 in character, and the other was, as already noted (C. salina), loaded with salts of lime. 

 At Monkwearmouth Colliery it occurred in company with Cypridopsis vidua, Cypris 

 reptans, C. salina, Daphnia vecula, &c. ; at Hylton Dene with C. gibba, C. compressa, 

 Candona Candida, Mysis vulgaris, Palcemon varians, Coropliium longicorne, and many 

 freshwater plants and animals ; at Warkworth with Cypris salina, Cytheridea torosa, 

 Chydorus sphcericus, and Daphnia vetula ; at Gravesend with C. gibba, Candona Candida, 

 Cytheridea torosa, and Crangon vulgaris. 



The only brown specimens I have seen were from Gravesend, Grimsby, and Wark- 

 worth ; these have the appearance of being coloured by dirty water. 



