OOPEPODS OF THE WOODS HOLE REGION 



217 



four spines; distal segment of fifth legs foliaceons, as wide as long, 

 overlapping the basal expansion, with seven large setae, third inner 

 one filiform; basal expansion reaching beyond center of distal seg- 

 ment, with five setae, all plumose, middle one longest. Total length, 

 0.9-1.1 mm. 



Male. — Second basipod of first legs with a slender and nearly 

 straight inner spine, reaching beyond the center of the basal endopod 

 segment; endopod of second leg nearly as long as exopod, its end 

 segment with a slender apical spine, curved outward, and two stout 

 outer spines, the proximal one widened ; distal segment of fifth legs 

 as wide as long, with six setae, the third outer one filiform; basal 



Figure 144. — Amphiascus 

 obscurus: a, Male, endo- 

 pod of second leg ; h, fe- 

 male, fifth leg ; c, male, 

 fifth leg 



Figure 145. — Amiyhiaseus lonffiros- 

 tris: a, Male, endopod of second 

 leg ; b, female, fifth leg ; C, male, 

 fifth leg 



expansion very short, with two equal apical setae. Total length, 

 0.75-0.9 mm. 



Remarks. — When alive this species can be easily distinguished by 

 its color; when preserved the seven large setae on the dis'.al segment 

 of the fifth legs furnish the best single character. The presence 

 of the species in the brackish ponds on Chappaquicldick Island shows 

 that it is probably well distributed elsewhere in the area. 



AMPHIASCUS LONGIROSTRIS (Glaus) 

 FlGtTBB 145 



Dactylopus longirosfris Claus, Die frei lebenden Copepoden, p. 127. pi. IS, 186.?. 

 Amphiascus longirostris Sars, Crustacea of Norway, vol. 5, p. 159, pis. 100, 101, 

 1906. 



Occurrence. — Twenty specimens, including both sexes, were taken 

 in one of the brackish ponds on Chappaquiddick Island, August, 1926, 



