COPEPODS OP THE WOODS HOLE EEGION 317 



antennae just reaching the posterior margin of the third metasome 

 segment. Outer margin spines on the three exopod segments of the 

 first three pairs of legs 1, 1, 3, respectively; on the fourth legs 

 1, 1, 2; fifth leg with a single apical seta and none on the side of 

 the fifth segment. Total length, 0.5-0.65 mm. 



Male. — Body shorter and stouter than in the female; groove 

 between the first and second thoracic segments with a median dorsal 

 sinus; no process on penultimate segment of first antenna; second 

 abdominal segment longer than wide ; length of last three abdominal 

 segments as 10 : 9 : 6. End segment of exopod in first three pairs of 

 legs with three outer spines, in fourth legs with two spines. Total 

 length, 0.48-0.57 mm. 



Reviarks. — This species may be recognized at once by the squarely 

 truncated forehead and the absence of a rostrum. Furthermore, the 

 first antennae are shorter than in any of the other species. It is 

 apparently a straggler into the area from the south and is not 

 likely to occur in any great numbers. 



Family CYCLOPINIDAE 

 Genus CYCLOPINA Claus, 1863 



Body of usual cyclopoid form; urosome 4-segmented in female, 

 5-segmented in male. First antennae slender, 10-segmented in fe- 

 male, 14-segmented and twice geniculate in male; second antennae 

 4-segmented, without an exopod ; mandibles with serrate teeth and a 

 biramose palp ; first maxillae with a well-developed masticatory lobe 

 and a lamellar palp ; second maxillae stout, the terminal part 3-seg- 

 mented, the basal part 1-segmented; maxilliped rather slender, the 

 distal portion made up of three sparsely setose segments. Rami of 

 first four pairs of legs 3-segmented, the exopod spines broad and 

 flanged, and numbering 6, 7, 7, and 5 ; fifth legs 2-segmented in both 

 sexes, armed with spines and filiform setae; middle segment of first 

 endopod witli a single seta. Two ovisacs, subcylindrical ; eggs large 

 and few in number. A single species, 



CYCLOPINA AGILIS. new species 



Plate 22 



Occurrence. — Fifty specimens, including both sexes, most of the 

 females carrying ovisacs, were washed from the sand on the shore 

 of Katama Bay, Marthas Vineyard, August, 1927. The male holo- 

 type is U.S.N.M. No. 63438. 



Color. — Body semitransparent, whitish, often tinged with blue; 

 ovaries, oviducts, and eggs greenish blue ; eye dull red. 



Female. — Body cyclopoid, metasome elliptical, strongly arched 

 dorsally, and flattened ventrally. Head fused with the first seg- 

 71937—32 22 



