of British Entomostraca. 415 



Genus Candona. 

 Sp. 1. C. similis, n. s. PI. IX. f. 4. 



Shell somewhat elliptical in figure, flattish, slightly sinuated in 

 middle of anterior edge, white with two dark orange-coloured 

 spots on the back. It is smooth, except round the edges, which 

 are beset with some rather stiff hairs, more numerous at anterior 

 extremity than posterior, transparent, rather larger at anterior 

 extremity than posterior. The feet have one long curved claw 

 and one short. Pediform antennse (f. 4 a) have three strong 

 curved claws at their extremities, but no bundle of long setae. It 

 creeps upon the plants, &c. at the bottom of the water, and when 

 it walks it leisurely puts first one foot forward, then the other. 



It approaches Cypris detecta, Miiller; the posterior extre- 

 mity however is narrower than the anterior, which is the reverse 

 in the detecta. 



Hah. Pond on Clapham Common. 



Section 3. Copepoda. 



The genus Cyclops of Miiller, composed of very heterogeneous 

 materials, required reform, and has accordingly been reviewed by 

 M. Edwards, who, in his great work on the Crustacea, distin- 

 guishes three different ^-enera. The characters of these he takes 

 from the structure of the second or inferior pair of antennae and the 

 foot-jaws. In his genus Cyclopsina however he includes two spe- 

 cies of Cyclops described by Miiller, which are very different from 

 each other and cannot be placed together. The chief character of 

 the genus Cyclopsina is the branched nature of the second or in- 

 ferior pair of antennse, a character which agrees well with the 

 structure of these organs in the Cyclops cceruleus of Miiller, but 

 not with his C. minutus, in which the inferior antennae are sim- 

 ple and not branched. I propose dividing this family into the 

 following genera : — 



Fani. CYCLOPIDJi. 



Head distinct from body, not possessing a moveable beak ; 

 body consisting generally of four, abdomen of six segments ; foot- 

 jaws two pairs, sometimes small ; legs about five pairs ; one eye. 



Genus 1. Cyclops, Miiller. 

 Foot-jaws large and strong, branched ; second or inferior pair 

 of antennse simple ; external ovaries double. 



The C. quadricornis, Mlill., is the type of the genus. 



Genus 2. Cyclopsina, M. Edwards. 



Foot-jaws of considerable magnitude, simple ; second or infe- 

 rior pair of antennse branched ; external ovary single. 



The Cyc. cceruleus, Miiller (Monoc. Castor, Jurine), is the type 

 of this genus. 



