170 BRITISH ENTOMOSTRACA. 



4. Cythere alba. Tab. XX, fig. 6. 



Cythere alba, Baird, Trans. Berw. Nat. Club, i, 98, t. 3, f. 6,1835, 

 and ii, 153 ; Mag. Zool. and Bot., ii, 143, t. 5, f. 24. 

 — M. Edwards, Hist. Nat. Crust., iii, 409. 



Shell obovate, the anterior extremity much broader 

 than the posterior, fringed round the edges with short 

 hairs. The colour is white, and a margin extends all 

 round the outer edge still whiter than the body of the 

 shell. The valves are transparent, showing the dark body 

 of the insect shining through. 



Hab. — Sea-shore at Dunbar, East Lothian, 1835. 



5. Cythere variabilis. Tab. XXI, figs. 10, 11. 



Cythere variabilis, Baird, Trans. Berw. Nat. Club, i, 98, t. 3, 

 f. 7, a, b, 1835, and ii, 153, ; Mag. Zool. 

 and Bot., ii, 143, t. 5, f. 25, a, b. 

 — M. Edwards, Hist. Nat. Crust., iii, 409. 



Shell oval, the anterior extremity considerably narrower 

 than the posterior, glaucous, without hairs. This species 

 varies much in colour and markings ; some individuals are 

 white, with two black fasciae running transversely across 

 the shell, one at the posterior margin, the other across the 

 centre of the valves, while the posterior extremity is marked 

 besides by a beautiful reddish or bright bronze spot. 

 Others are of a light flesh colour, with the edges of the 

 shell slightly greenish, and the central portion marked 

 w\\\\ dark streaks running across. Some again are alto- 

 gether of a fine flesh colour, without any marks upon the 

 valves, while others are of a uniform dark brown or almost 

 black hue. All these varieties, however, agree in shape, 

 size, &c. 



Hah. — Coast of Berwickshire ; common ; Dover, Sept. 

 1849. 



