COPEPODS OF THE WOODS HOLE REGION 457 



Male. — Carapace longer than wide ; stylif orm process reaching the 

 posterior margin of the second segment; second, third, and fourth 

 segments about the same length and width; fused fifth and genital 

 segment shorter than the free thorax and only three times as long as 

 wide. Abdomen 3-segmented, the two basal segments about the same 

 length, the anal segment a little shorter. Caudal rami longer than 

 the anal segment, twelve times as long as wide, each tipped with three 

 long plumose setae. Total length, 5-5.5 mm. 



Remarks. — Beneden claimed to have found the rudiments of a fifth 

 pair of legs at the posterior corners of the genital segment, but Claus 

 disproved this. The species can be recognized by the angular front 

 corners of the lateral areas of the carapace and the length of the 

 stylif orm processes. 



KR0YERINA, new genus 



Female. — Carapace triangular, strongly narrowed anteriorly, wid- 

 est near the posterior margin, without posterior lobes and sinuses or 

 styliform processes, and with or without a cephalic area. Second, 

 third, and fourth segments about the same length and width, the 

 latter scarcely more than half the width of the carapace. Fifth and 

 genital segments fused, nearly as wide as the carapace, without pos- 

 terior lobes or with very short ones. Abdomen 2-segmented, basal 

 segment much shorter than terminal; caudal rami narrow and elon- 

 gate, each tipped with three setae. First antenna 6-segmented; 

 second antennae chelate; maxillipeds with a strongly curved apical 

 claw. All four pairs of legs biramose, rami 3-segmented. 



Male. — Similar to the female, but smaller; carapace about as long 

 as wide ; fused fifth and genital segment relatively shorter ; abdomen 

 3-segmented, anal segment less than half the length of the basal seg- 

 ment and considerably narrower; caudal rami longer than the anal 

 segment and slender; antennae, mouth parts, and legs like those of 

 the female. 



Genotype. — Kr^i/erina nusuta, new species. 



KEY TO THE SPECIES (FEMAI^S) 



1. Fused fifth and genital segment less than four times as long as 



wide, its posterior corners prominent nasuta, new species (p. 457) 



Fused fifth and genital segment more than eight times as long as 

 wide, its posterior corners smoothly tapered- elongata, new species (p. 459) 



KR0YERINA NASUTA, new species 



Plate 31, a-fc 



Occurrence. — Four females from spiracles of large sting ray 

 {Dasyhatius 7}im^inics), July 18, 1923; a female with attached male 



