779 



95 (96) 



COPEPODA 



Furcae of variable length, armtd cxitrnally with a njw - 

 spines; very common. . . Cyi lops srrruJutus I is^ht:: 



The loiiK twelve scxmcntctl antennae uui thr trt 



rate marKine<l furral rami M-nc u> «lf- ' •' 



species. The fiKure i»f ihi- alHlonjrn 'I 

 acteristic structure of the f ureal r.tn- 

 gocxl deal of variation in the : 

 When scrrulalus is limnetic in 

 rami are lonj,' and slen<ler; ihi^ 

 variety clt'Kans Herritk. When il iivcs m i- 

 littoral waters, the furcal rami arc <ih<irt an ■ 

 this form is known as varir'- ' ' " 



abdomen l'if,'ure<l may he m; 

 latus, dedans hc'\i\^, mut.\\ lu 



sfwndingly shorter. Found every wiicri: liic »u*U over. 

 Length of female, o.8 to 1.25 mna. 



Fig. 1226. Cyclops serrulatus. A, abdo- 

 men of female. X 67. B, fifth foot of 

 same. X 213. (Original.) 



96 (95) Furcae short, without lateral row of spines. 



Cyclops prasinus Kischcr iH/x>. 



It is a minute limnetic form. It resembles serruiaius in \is lonx twdvr- 



segmented antennae, but its abdomen is ver>' different. The fun .-J 



resemble leuckarti in the fact that the lateral seta is jjlace*! at a\> 

 way of the length, but the species is distinguishe<l at a glance, not ■ 

 its smaller size, but by the fact that the antennae are comiiosc<l 0/ t^cl'.c 

 segments. Cyclops prasinus is widely distril)ulc>d. esixxially in ibc laxxrr 

 bodies of water. It is common in the Great Lakes. 

 Length of female, 0.48 mm. 



Fig. 1227. 



Abdomen of female Cyclops prasinus. X I37- (Ori«iaaL) 



07 (04) Fifth feet armed with one seta, swimming feet of two scgmcnls. 



Cyclops varUijfts SAn> \^ 3. 



Cyclops varicans occurs in Panama and Guatemala, but there are no authentic rrcurU* ol it« 

 occurrence in the United States. 



98 (77) Antenna composed of eleven segments or less 99 



99 (102, 103) Antennae composed of eleven segments 100 



100 (loi Rami of swimming feet composed of ^l^^'/^'P"^^^-"-, ., . . . 



Cyclops pitiilcratus Koch i^js. 



This stout dark-colored species is not uncommon in shallow Ukr» and 



.inant S^is and is readily recogni.cHl by the character, pvcn m ihc key. 



Length of female, i.i mm. 



stagnant pools, and 



Fig. 1228. Abdomen of female Cyclops pkaUratus. X 69. (l)ri«in*U 



