NOETH AMERICAN PLANKTON. 79 



the seven teeth being bifid, a curved claw-like spine 

 forming the apex of a separate lobe. Basal portion of 

 the palp large, the two setose branches being 2 and 

 4-jointed respectively. 



The posterior foot jaws (fig. 5) are stouter than in most 

 of the Calanina? ; the fine smaller terminal joints are 

 densely setose. The second joint has four non-plumose 

 setaB, and the basal joint three pairs of plumose setae. 

 Inner branch of 1st pair of swimming feet is 1-jointed, 

 that of the 2nd, 3rd, and 4th 2-jointed (figs. 6 and 7). 

 The 5th feet are jointed similarly to E. a finis. The 

 penultimate joint in the female is much the longest, 

 and is produced on the inner side downwards into a long 

 spear-like spine extending beyond the spine of the terminal 

 joint, and provided with short sharp teeth on each side 

 (fig. 8). 



The 5th feet of the male (fig. 10) are less robust than in 

 E. affinis, the joints being more slender. The abdomen is 

 3-jointed in the female and 5 in the male (fig. 11) ; the first 

 segment in the female has a conspicuous obtuse projection 

 on each side posteriorly. Caudal stylets, long and narrow, 

 with one lateral seta and four terminal setse on each 

 stylet, all finely plumose. 



Males and females of this new species were found 

 plentifully in association with E. affinis in the St. 

 Lawrence, between Quebec and Kimouski. The penulti- 

 mate joint of the abdomen in the female readily dis- 

 tinguishes it from the other species of the genus. 



It is with peculiar pleasure that I. C. Thompson and 

 A. Scott associate with this striking Copepod the name 

 of Prof. Herdman, who collected the material upon which 

 this paper is based, 



