COPEPODS OP THE WOODS HOLE REGION 



177 



ment of fifth leg reaching tip of distal segment, its outer seta twice 

 the length of the inner one; inner seta of distal segment one-eighth 

 as long as the other two, which are about equal. Total length, 0.4- 

 0.5 mm. 



Male. — Smaller than female; genital segment completely divided 

 at the center; caudal rami a little wider than long; first antennae 

 geniculate, the distal portion made up of the last two segments; 

 fifth legs like those of the female. Total length, 0.3-0.4 mm. 



Remarhs. — This minute species is common throughout the entire 

 Atlantic; it may be distinguished by its minute size and the fact 

 that the body is laterally compressed and usually lies upon its side, 



MICROSETELLA ROSEA (Dana) 

 FlGUKE 122 



Canthovamptus roseus Dana, United States Exploring Expedition, 1838-1842 



(Wilkes), vol. 14, Crustacea, p. 1189, 1853, pi. 83, fig. 10, 1855. 

 Microsetella rosea Gies- 



BRECHT, Fauna und Flora 



des Golfes von Neapel, 



vol. 19, p. 554, pi. 44, 1892. 



Occurrence. — T en f e - 

 males taken in surface 

 tow in Woods Hole Har- 

 bor, July, 1926. 



Dist7%ution. — Sulu Sea 

 (Dana) ; Naples (Gies- 

 brecht) ; English seas 

 (Brady); Woods Hole 

 Harbor (Fish). 



Color. — Body transpar- 

 ent, with a decided rosy or 

 reddish tinge, which is 

 deepest anteriorly and 

 gradually fades away 

 posteriorly. 



Female. — Body as strongly compressed as in the preceding species 

 and nearly twice the size; second, third, and fourth metasome seg- 

 ments and the three abdominal segments with tranverse rows of 

 spinules near the anterior margins ; second inner apical seta of each 

 caudal ramus nearly twice the body length. Inner expansion of 

 basal segment of fifth legs reaching the tip of the distal segment, its 

 apical setae about equal in length, its outer process very plump with 

 two rows of small spinules running longitudinally; distal segment 

 with an accessory seta on the posterior surface near the center. Total 

 length, 0.65-0.85 mm. 



Male. — Unknown. 



Figure 122. — Microsetella rosea: a. Female, dorsal 

 (after Giesbrecht) ; }), female, fifth leg; c, female, 

 first antenna 



