212 



BULLETIISr 15 8, UlSTITED STATES NATIONAL MUSEUM 



genital segment divided; the longest caudal seta more than twice 

 the length of the iirosome. First antennae 6-segmented, the termi- 

 nal portion made up of two segments; basal expansion of fifth legs 

 reaching beyond the tip of the distal segment and armed with five 

 slender setae, the second outer one the longest; distal segment small 

 oval, with one elongated apical seta, three on the outer, and one on 

 the inner margin. Total length, 0.4-0.55 mm. 



Blale. — Distal segment of second endopod elliptical, with two ter- 

 minal spines, the inner one broad and dagger-shaped, and one on the 

 outer margin, also dagger-shaped; basal expansion of fifth legs 

 smaller than in the female, not reaching the tip of the distal seg- 

 ment and armed with three setae, two apical and one at the center of 

 the inner margin. Total length, 0.3-0.45 mm. 



Figure 141.- — Pseudothalestris miii- 

 iita: n. Female, lateral (after 

 Sars) ; 1), female, fifth leg ; c, male, 

 fifth leg ; d, male, endopod of sec- 

 ond leg 



Figure 142. — Pseudothalestris pyg- 

 maca: a, Female, lateral (after 

 Sars) ; 6, female, fifth leg; c, male, 

 fifth leg ; d, male, endopod of sec- 

 ond leg 



Remarks. — This species can be separated from the other two by 

 the details of the fifth legs, and by the 6-segmented first antennae. 

 Sars made the following curious statement with reference to this 

 copepod when alive : " When disturbed, the animal secretes a clear 

 viscid fluid in considerable quantity. From which organ this matter 

 is derived I have not yet been enabled to determine." 



PSEUDOTHALESTRIS PYGMAEA (T. Scott) 



Figure 142 



Pseudoiveshvoodia pygmaca T. Scott, Ann. Mag. Nat. Hist., ser. 6, vol. 15, p. 



55, pi. 6, 1895. 

 Westwoodia pygmaea Sars, Crustacea of Norway, vol. 5, p. 143, pi. 88, fig. 2, 



1906. 



Occurrence. — A single female was taken in a surface tow in Little 

 Harbor, Woods Hole, September, 1881, by Eathbun. 



Distribution. — Scottish coast (T. Scott) ; coast of Norway (Sars). 



