COPEPODS OF THE WOODS HOLE REGION 



227 



genital segment divided only laterally; caudal rami twice as wide 

 as long, inner apical seta moderately thickened at its base. 



First antennae 8-segmented, two basal segments swollen, end 

 segment as long as the three preceding segments combined ; first ex- 

 opod nearly as long as entire endopod, without any inner setae; end 

 segment of third exopod with four spines and two setae ; distal seg- 

 ment of fifth legs oval, considerably 

 tapered distally, with five setae, the 

 middle one alone apical and fili- 

 form; basal expansion triangular, 

 nearly reaching the tip of the distal 

 segment, with five setae, all except 

 the inner one sparsely plumose. 

 Total length, 0.7-0.8 mm. 



Male. — Second basipod of first 

 leg with a broad tenonlike spine, 

 rounded at its tip, on the inner mar- 

 gin ; end segment of second endopod 

 with an inner fingerlike process, two 

 stout outer teeth, a wide bayonet- 

 shaped apical spine, and a more 

 slender inner spine, widened and 

 bidfid at its tip. 



Remarks. — The species may be 

 recognized by the notch at the tip 

 of the rostrum, and by the structure of the first and fifth legs. It 

 has never before been reported from American coasts. 



AMPHIASCUS COMMENSALIS Seiwell 

 Figure 153 



Amphlascus commicnsalis Seewell, Proc. U. S. Nat. Mus., vol. 73, art. 18, p. 2, 

 pi. 1, 1928. 



Occurrence. — Both sexes were taken from the common sea pork, 

 Amaroucium, collected near Woods Hole. 



DistHhution. — Not found outside the present area. 



Color. — Body a uniform yellowish gray without other pigmenta- 

 tion. 



Female. — Body slender, the metasome scarcely wider than the uro- 

 some ; cephalic segment as long as the rest of the metasome ; ros- 

 trum lanceolate; urosome as long as metasome; caudal rami shorter 

 than anal segment, with short setae. Basal segment of first an- 

 tenna much the longest ; exopod of second antenna 2-segmented with 

 four setae, attached to side of basal segment of endopod. Inner ex- 

 pansion of basal segment of fifth leg narrow, not reaching center of 



FiGUKB 152. — Amphiascus intermedlus : 

 a. Female, dorsal (after Sars) ; V, 

 female, fifth leg ; c, rostrum 



