16 PROCEEDINGS OF THE NATIONAL, MUSEUM vol. 82 



with the Delaware River and is affected by the tides. With E. 

 hirundoides were found some Cyclops species that are common in 

 fresh water. 



Remarks. — Nordquist noted that E. hii^imdoides is a form in- 

 termediate between E. affinis and E. Jiirundo and that in its varia- 

 tions it is coiuiected with both species. Some authors have thought 

 both E. hirundo and E. hirundoides should be considered as varie- 

 ties of E. afjinis. Inasmuch as the names cover distinct characteris- 

 tics, it has seemed best here to give them specific rank, although it 

 is recognized that they are closely related. 



While E. a/Jinis is found in both fresh and salt water, E. hirwn- 

 doides apparently does not occur in water that is entirelj^ fresh. 



EURYTEMORA JOHANSENI Willey 



Plate S, Figures 4, 7 

 Eurytemora joha^seni Willey, 1920, p. 13K, figs. 5-7, 9, 11-13. 



The wings of the last cephalothoracic segment are produced dis- 

 tad but do not reach the end of the first abdominal segment. (PI. 

 8, fig. 4.) The first abdominal segment is expanded about midway of 

 its length. The second and third segments and the furcal rami are 

 of about equal length. The first antennae about equal the cephalo- 

 thorax. In the fifth feet of the female (pi. 8, fig. 7) the unguiform 

 process of the second segment of the exopod extends distad, but is 

 not so long as the second segment ; it is dentate on the inner border. 



Length : Female, 1.28 mm ; male, 1.12 mm. 



Occurrence. — Described from collections of the Canadian Arctic 

 expedition. 



Genus EPISCHURA Forbes, 1882 



Cephalothorax more or less distinctly 6-segmented. Abdomen in 

 the female composed of four segments, in the male of five. Abdomen 

 of the male more or less asymmetrical and in most species bent to the 

 right; processes forming a prehensile apparatus projecting to the 

 right ; these processes, in E. haikalensis and E. chanhensis^ are found 

 clearly only on the fifth segment, in the other species on the second, 

 third, and fifth. The furcal rami are ciliate on the inner margin 

 and each is armed with a short outer spine, a slender inner seta, and 

 three plumose setae of about equal lengih. 



The first antennae (pi. 9, fig. 1) are 25-segmented, the last segment 

 short; the right male antenna (pi. 9, fig. 2) is 22-segmented, genicu- 

 late between the eighteenth and nineteenth segments, the segments 

 preceding the geniculation being slightly swollen. 



The exopod of the second antenna is 7-segmented, with three short 

 central segments (pi. 11, fig. 1) and a short terminal segment. The 



