ANATOMY AND SIETAMORPHOSIS OF CYCLOPS. 227 



c. The appendages. 



1. The large jointed first antennae have been already 

 noticed. They are the principal locomotor organs, and 

 are seen, in a side view, to be the first or most anterior 

 pair of jointed appendages. 



2. Next posterior to these are the second antennae, 

 which have already been noticed. 



3. On the sides of the mouth are the 

 stout, blunt, dark-colored mandibles 

 (Fig. 119). 



Fig. 119. — Mandible of Cyclops canthocar- 

 poides. (From Claus.) Fig. 119. 



Fig. 120. 



4. Behind these are the incurved setose 

 first maxiUcB (Fig. 120), which, like the 

 mandibles, have cutting edges. 



Fig. 120. — First maxilla of Cyclops canthocarpoides. 

 (From Claus.) 



5. The second maxiUce (Fig. 121) are jointed, and con- 

 sist of two portions, the exopodiie {ex.'), which is much 

 the larger, and, in a side view, is anterior to the smaller- 

 jointed endopodite {en). These parts are mounted upon 

 a protopodite, which, as well as the exopodite and endopo- 

 dite, carries plumose setae. The proximal portion of the 

 exopodite carries three distal joints, which are placed side 

 by side, and may be folded down upon the proximal por- 

 tion, like fingers bent down into the palm of the hand. 



6. Considerable space intervenes between the mouth- 

 parts and the thoracic appendages, of which there are five 

 pairs, the four anterior pairs being about equal in size, 

 and the fifth pair rudimentary. The first pair of limbs 



