CYCLOPOIDEA. ;Qgj 



In a view from above the jointed appendages are often concealed from 

 sight excepting the two pairs of antennae. The anterior antennas extend 

 laterally from either side of the head, usually with a double curva- 

 ture, like either half of a bracket ( v — v — '). The posterior pair are 

 either projected laterally, just behind the posterior, or else anteriorly, 

 so as to appear in front of the head ; and by means of the setae, which 

 may be spread or closed like the fingers of a hand, the animals may 

 attach themselves to objects. 



Cyclops brasiliensis. 



Cephalothorax posticb obtnsus, abdominem longitudine superans. An- 

 tennas anticce in utroque sexu elongates {cephalothorace longiores), arti- 

 culis primo secundoque majoribus et setis oblongis apice instructis, setis 

 antennarum aliis brevibus; maris 1 -articulator, articulis tribus basali- 

 bus crassissimis, reliquis teretibus; feminae, 14:-articulatce, teretes. 

 Styli caudales oblongi, tres articulos abdominis ultimos simul sumtos 

 fere cequantes; seta secunddfere abdominis longitudine, prima dimidio 

 breviore. 



Cephalothorax having the posterior angles obtuse, longer than the 

 abdomen. Anterior antennae of both sexes longer than cephalo- 

 thorax, first and second joints largest and furnished with oblong 

 setae at apex, other setae of the antennae short. Antennae of male 

 seven-jointed, three basal joints very stout, the rest terete. An- 

 tennae of female fourteen-jointed, terete. Caudal stylets oblong, as 

 long as the last three abdominal joints ; second seta nearly as long 

 as abdomen, the first one-half shorter. 



Plate 83, fig. 1 a, male, enlarged ; Z>, lateral view, showing the beak 

 and alimentary canal; c, second pair of antennae; d, extremity of 

 maxillipeds; e, one of the natatory legs; f female antenna; g, abdo- 

 men, with external ovaries of female. 



At Kio Janeiro, in stagnant pools, December, 1838. 



The specimens of this species collected were colourless. Eyes 

 placed on a large spot of pigment, of a reddish black colour. Abdo- 



296 



