170 BRITISH ENTOMOSTRACA. 



3. CYTHEREIS ANTIQUATA. Tab. XX, fig. '2. 



Shell oblong, very thick, rough with granulations, and 

 having two or three thick crests or ribs running along tin- 

 centre of the valves. One extremity is flattened, and has 

 four short, stout teeth springing from its edge ; the other 

 is more convex and rounded. The whole circumference 

 is wrinkled, and the shell presents a very antiquated 

 appearance. 



Jlab. Isle of Skye, in sand ; W. C. Williamson, Esq. 



Family 2 CYPRIDINADJS. 



Character. Eyes two, pcdunculated. Antennae, two 

 pairs, both peditbrm. Eect two pairs ; one pair always 

 inclosed within the shell, and of a very peculiar structure. 

 Abdomen terminated by a broad lamellar plate, armed 

 with strong claws and hooked spines. 



Genus CYPRIDINA. 



CYPRIDINA, M. Edwards, Lamarck, Hist. Nat. An. s. "Vert., 2d edit., 



v, 178, note, 1838 ; Hist. Nat. Crust,, iii, 409. 

 Baird, Ann. and Mag. Nat. Hist., 2d scries, i, 21. 

 Dana, Conspcct. Crust., 50. 

 CYPRELLA (not CYPRIDINA), Bosquet, Eutomost. de la Craio dc 



Maestricht. 

 ASTEROPE, PMlippi, Ann. Mag. Nat. Hist, (fide Dana in litcris.) 



As there is but one genus, the character given above 

 for the family will suffice for it also. 



The genus Cypridina was founded by M. IMwards in 

 1838, in a note to the genus Cypris, in the fifth volume 

 of Lamarck's 'Hist. Nat. An. s. Verteb.,' and was after- 

 wards more fully detailed in the third volume of his ' Hist. 

 Nat. Crust.' The animal resembles a good deal in its 

 general form ami structure that of the Gypris, while the 

 shell at first sight might easily he mistaken for one of that 

 uciuis. It has, however, two eyes, distinct from each 

 other; t\\o pairs of autenn;e, both peditbrm ; one pair of 

 natatory feet ; and a peculiar organ, apparently for sup- 

 porting the o\a, similar in purpose to, but differing in 



