ENTOMOSTKACA OF MINNESOTA. 89 



* First joint of the fifth foot broad. . . viridis, 90; americanilS, 91; 

 iDgeiis, 92; verualis, 92; robustiis, 93; parens, 93; 

 brevispiuosus, 95; nniaiigulatus, £6; leuckarti, 96; 

 scourfleldi, 98; oithonoides, 98; dybowskii, 99; 



bisetosus, 99. 

 ** First joint of the fifth foot longer than wide. 



t Terminal segment of the fifth foot with one long seta and 



oae short spine strenuiis, 99; laciistris, 101. 



ft Terminal segment of the fifth foot with two rather long setjc, 



piilcliellus, 101; niiunilus, 103; forbesi, 104. 



ttt Terminal segment of the fifth foot with three set se. . signatllS 105; 



var. coronatus, 106; var. temiicornis, 106. 



III. Antennte 16-jointed, laiiguidus, 107; iiiodestiis, 103; capilliferus, 109; 



IV. Antennae 14-jointed iusigrilis, 110. 



V. Antennte 12-jointed. 



a. Fifth foot one- jointed. . . . sernilatn.s, 111; var. elegaiis, 112. 



macrurus, 113; prasimis, 113; fiuviatilis, 114. 



b. Fifth foot two-jointed. . . . capillatus, 115; crassicaudis, 115; 



varicans, 116. 



VI. Antenna) ll-jointed. . . gracilis, 117; diaphanus, 117; affiiiis, 117; 



bicolor, 118. 



VII. Antenna) 10-jointed phaleratiis, 120. 



VIII. Antenna) eight-jointed liinbriatus, 121. 



IX. Antenna) six-jointed iBquoreus, 122. 



The forms which have been reported with 18 jointed antennae may 

 not necessarily be representatives of a single species but may be spor- 

 adic instances of reduplication in the antennal segments on the part 

 of various 17-jointed forms. Cyclops elongatus Claus, the only named 

 species with 18-jointed antennae, is confidently identified with C. ver- 

 nalis Fischer, bySchmeil, nevertheless Claus' description is as follows: 

 "Length of body 2.5 mm., elongate, gradually narrowed toward the 

 end. The anterior antennie 18 jointed, differing from the 17-jointed 

 type by the separation of the seventh joint into two; they do not ex- 

 tend far beyond the first segment of the cephalothorax. The fifth ab- 

 dominal segment is strongly toothed. Rudimentary foot two-jointed, 

 with relatively small basal joint and elongate terminal one, on whose 

 apex is one long and one short seta. The stylets are longer than the 

 two last abdominal segments, with relatively short setie, whose rel- 

 ative size is nearly like those of C. cuspidatus.'" 



This species is reported by Cragin from near Cambridge, but has 

 been seen by no other observer except the describer. 



* Cyclops ater Herrick. 

 Plates VI, Figs. 11, 12; XII, Figs. 9-12; XXI, Figs. 13-15, 17, 18. 

 Herrick '82, '84, '87; Turner '92. 

 Cephalothorax very large and broadly oval and usually conspicu- 

 ously colored. Antennoe as long as the cephalothoiax (1.2 mm.), 



