COPEPODS OF THE WOODS HOLE REGION 319 



axis, and hence are usually visible in dorsal view. The outer seta 

 on the basal segment reaches nearly to the tip of the apical seta on 

 the end segment and is smooth, without plumes. Total length, 0.35- 

 0.45 mm. 



Male. — Body more slender and shorter than that of the female, 

 the second, third, and fourth segments are but little narrowed, the 

 fifth segment is abruptly contracted to half the width of the fourth 

 segment. Urosome scarcely half the length of the metasome ; genital 

 segment widest posteriorly; abdomen made up of four segments 

 about equal in length. First antennae very indistinctly segmented, 

 apparently made up of 12 or 13 segments, powerfully developed 

 and twice hinged, the proximal elbow very prominent, the terminal 

 portion of two segments, the last one turned forward at right angles 

 to the one j)rec€ding it. The third and fourth segments each carry 

 a short spine on the posterior margin; the sixth segment, at the 

 proximal elbow, has a triangular process on its outer margin, and 

 at the base of the process on the dorsal surface are three stout setae. 

 The second antennae, mouth parts, and swimming legs are like those 

 of the female. The fifth legs are also similar, but the inner spine 

 of the terminal segment is short and blunt, and the outer spines are 

 longer and more slender; the apical seta is the same, elongate, and 

 filiform. Total length, 0.3-0.4 mm. 



Remarks. — This species may be recognized by the structure of the 

 two pairs of antennae and the fifth legs. It is rather unusual to 

 find a cyclopid in such a habitat, especially as no marine vegetation 

 of any sort was present. But the large number of specimens ob- 

 tained by washing a comparatively small quantity of sand leaves 

 no doubt that this was their natural habitat. When disturbed the 

 copepod darts about with great agility but quickly settles in another 

 place, never remaining in motion for any length of time. 



CYCLOPINODES, new genus 



Body more elongate and narrower than in Oyclopina; urosome 

 4-segmented in female, 5-segmented in male. First antennae with 

 20 more or less distinct segments in female, 16-segmented and twice 

 geniculate in male ; second antennae 4-segmented, without an exopod. 

 Mandibles with serrate teeth and a biramose palp; terminal section 

 of second maxilla 3-segmented, basal section 2-segmented ; maxilliped 

 slender, its terminal section made up of four densely setose segments. 

 Rami of first four pairs of legs 3-segmented, the exopod spines small 

 and narrowly flanged, those on the end segments numbering 3, 4, 

 4, and 3, respectively; middle segment of first endopod with two 

 setae; fifth leg 3-segmented in female, 4-segmented in male, armed 



