72 



KANSAS ACADEMY OF SCIENCE. 



dal setre fine, short, and sparsely set. First anteuuse seventeen-jointed, and 

 about as long as the first body-segment. The armature of the basal and 

 middle joints of the swimming-feet is the same as in the C. Thomasi. That 

 of the apical joints is as follows: 



Tex., two spines. 



Outer branch < ap., twoset;e. 



(in., three setie. 



Tex., three spines. 



Outer branch -l ap., one spine, one seta. 



(in., three settc. 



f ex., three spines. 



Outer branch -; ap., one spine, one seta. 



(in., three seiie. 



Inner branch . 



Second Fool. 



Inner branch 



(ex., oni 



.-^ap.,??. 



(in.,??. 



f ex., on 



. -c ap., on 



(in., thi 



e seta. 



e spine, one seta. 



ree seta'. 



Third Fuot. 



Inner branch.. 



f ex., one seta. 



J ap., two subequal spines (inner 



I shorter). 



I^in., three seta'. 



Outer branch , 



[ex., 



^ap., 



(in.. 



Fourth Foot. 



three spines. 



one spine, one seta. 



three seta. 



fex., one seta. 



Inner branch -< ap., two subequal spines. 



(in., two setfe. 



Fifth foot bi-articulate. Basal joint wide and bearing a rather long plu- 

 mose seta at its outer angle. Apical joint small and narrow, bearing a long 

 plumose seia, and interior to the same a small seed-shaped spine shorter than 

 the joint itself. Ovisacs large, ellipsoidal, diverging, reaching posteriorly to 

 a point about even with the end of the furca, and containing many (about (?) 

 ninety) eggs. The color of the animal is dirty-white. Length, exclusive 

 of caudal setse, 1.55 ram. Cambridge, from a pool near the Museum of Com- 

 parative Zoology. 



Cyclops perarmaius sp. nov. (PI. I, figs. 9-18.) 

 First body-segment somewhat narrowed in front, and about as long as the 

 four and a half segments following. Posterior border of penultimate seg- 

 ment of thorax furnished at the sides with a minutely pectinate fringe. Sides 

 of the last thoracic segment finely ciliate, the stout spines of the fifth feet 

 projecting from beneath them. Abdominal and caudal segments greatly 

 foreshortened. Two small lateral protuberances at the anterior end of the 

 scarcely tapering first abdominal segment mark the situation of the vulvae* 

 Posterior border of last abdominal segment bearing a strong pectinate fringe. 

 Caudal segments about twice as long as broad, and sown on their inner sides 

 with short cilia, certain of which on either segment are placed in a double 

 row running obliquely outward and forward across the dorsal surface. Outer 

 of the two superior caudal sette quite short and remote from the apex of the 

 segment. Of the four apical setoe, the first and fourth are very short; the 

 second rather longer than the third, and about as long at the cephalothorax. 

 The first and fourth are ciliate-plumose. The second is plain at the base; 

 then sparsely and briefly spino-plumose, the pinnte becoming gradually 

 feebler toward the tip. The third is on the inner side, ciliate-plumose, ex- 

 cepting the plain basal portion, and on the outer .side ciliate-plumose at the 

 base; distad to this briefly spino-plumose as. in the second.. Eye large, dark 

 red, deeply notched in front. First antenntie eleven-jointed ; reaching about to 



