78 



ARIIIROPODA. 



tary pair, but attached to the abdomen. The head is tolerably 

 distinct, having one eye (occasionally two) and two pairs of an- 

 tennae, the latter sometimes differing considerably in the males, 

 and one pair acting as a natatory organ. The mouth is mandibu- 

 late. The young are naupliiform. The female has one, gene- 

 rally two, pendent ovisacs. 



The Copepoda are minute free-swimming Crustaceans, found 

 both in the sea and in freshwater. One species, Cetochilus septen- 

 trionalis, forms the principal food of the southern whales. It 

 also at times abounds on our coasts. Notodelphyidse are com- 

 mensals in the respiratory sac of Ascidians. 



Glaus places the Epizoa in the Copepoda; while Schmarda 

 ranks them as one of the two families composing the order 

 Lophyropoda ( = Copepoda). 



Misophria. 

 Oithona. 

 Cyclops. 

 Cyclopina. 



Harpacticida. 

 Thalestris. 

 Westwoodia. 

 Canthocamptus. 

 Harpacticus. 



Pettidiidte. 



Zaus. 



Peltidium. 



Alteutha. 



CalanidcB. 

 Cetochilus. 

 Calanus. 

 Temora. 

 Diaptomus. 



PontellidcB. 

 Irenaeus = Anomalo- 

 cera. 



Pontellfc. 



Notodelphyida. 

 Notodelphys. 

 Notopterophorus. 



AscidicolidcB. 

 Ascidicola. 



TSuproridcB. 

 Buprorus. 



Order II. OSTEACODA. 

 CROPHYROPODA. OSTRAPODA. CYPRIDACEA. 



Body not ringed, enclosed between two shell -like valves, and 

 terminated by a bifid tail. The inferior or second pair of an- 

 tennas natatory, Branchias attached to the oral appendages. 

 Two or three pairs of thoracic feet. 



The valves of the shell can be completely closed ; when open it 

 allows the play of the feet and antennas. The abdomen is rudi- 

 mentary. The eye is single (Baird), but this is due to the union 

 of two ; in Cypridinidac there are two movable pedunculate eyes. 

 There are no eyes in Halocypridae (Glaus). The young at once 

 assumes the shape of the parent. 



