l82 



COPEPODS OF LAST CRUISE OF CARNEGIE 



Corycaeus ovalis Claus 



[Coiycacus ovalis Claus, Die freilebenden Copepoden, p. 158, 

 1863.] 



Found at station i in the Atlantic and in widely separated 

 localities of the southeastern, central, and western Pacific. It 

 was present in 8 surface tows, 7 50-meter tows, and 2 100- 

 meter tows. The posterior processes of the fourth thoracic 

 segment are pointed, and the caudal rami are not longer than 

 the anal segment. 



Corycaeus pacificus F. Dahl 



[Corycaeus pacificus F. Dalil, Verhandl. Deut. zool. Gcsellsch., 

 vol. 4, Miinchen, p. 73, 1S94/'.] 



Not found in the Atlantic plankton, but very irregularly 

 scattered in the southeastern, central, and western Pacific. It 

 was present in 3 nocturnal and 5 diurnal surface tows, 13 50- 

 meter tows, and 13 100-meter tows. The posterior processes 

 of the fourth thoracic segment are bluntly rounded, some- 

 times almost circular. 



Corycaeus pumilus M. Dahl 



[Corycaeus pumilus M. Dahl, Ergebn. der Plankton-Exped. der 

 Humboldt-Stiftung, vol. 2, G. f i. Die Copepoden, p. gr, pi. 

 12, figs. 21-28, igi2.] 



Found at five Atlantic stations, and well distributed in all 

 regions of the Pacific except the north. Present in 12 noc- 

 turnal and 25 diurnal surface tows, 28 50-meter tows, and 25 

 loo-meter tows, another exceptionally even vertical distribu- 

 tion. In the female the metasome is nearly three times as 

 long as the urosome; in the male the cylindrical posterior part 

 of the genital segment is only one-third as long as wide. 



Corycaeus robustus Giesbrecht 



[Corycaeus robustus Giesbrecht, Atti R. Accad. Lincei, Rome, 

 ser. 4, vol. 7, sem. i, p. 480, i8gi; Fauna und Flora des 

 Golfes von Neapel, vol. 19, pp. 660, 673; pi. 51, figs. 38, 42, 

 1892.] 



Not found in the Atlantic plankton, and very irregularly 

 scattered over all regions of the Pacific except the north. It 

 was captured in i nocturnal and 6 diurnal surface tows, 9 

 50-meter tows, and 10 loo-meter tows. The genital segment 

 is much swollen laterally and notched near the center of each 

 lateral margin. The processes of the fourth thoracic segment 

 are squarely truncated posteriorly, and the anal segment is 

 much wider than long. 



Corycaeus speciosus Dana 



(Figure 41) 



[Corycaeus speciosus Dana, Proc. Anier. Acad. Arts and Sci., 

 vol. 2, p. 38, 1849; U. S. Exploring Exped., 1838-1842 

 (Wilkes), vol. 14, pt. 2, Crustacea, p. 1220, 1853; pi. 86, 

 fig. I, 1855.] 



Found everywhere in both oceans, except in the northern 

 parts and at stations sr to 64 in the South Pacific. Present in 

 8 nocturnal and 75 diurnal surface tows. 85 50-metcr tows, 

 and 66 100-meter tows. The caudal rami are as long as the 



urosome in the male, seven-eighths as long and widely diver- 

 gent in the female; genital segment of the female usually 

 arched dorsally. 



Corycaeus typicus (Kr0yer) 



[Agetus typicus Krciyer, Naturhist. Tidsskr., Kjobenhavn, ser. 

 2, vol. 2, p. 603, pi. 6, figs. 27-29, 1849.] 



Found in both oceans except in the northern part and the 

 extreme southern part (stations 59 to 61) of the Pacific. 

 Taken in 7 nocturnal and 27 diurnal surface tows, 41 50- 

 meter tows, and 39 100-meter tows. Processes of the fourth 

 thoracic segment standing up vertically and squarely trun- 

 cated posteriorly, each with a small tooth at the ventral corner. 



Genus DANODES, new genus 



Body short and stout; metasome pear-shaped and three- 

 fourths as wide as long; head fused with the first segment, 

 free thorax strongly tapered posteriorly; urosome much 

 shorter than metasome and relatively narrow. 



First antenna eight-segmented and short; second antenna 

 uniramose, four-segmented; mandible with setaceous palp; 

 lobes of first maxilla very unequal in size; second maxilla and 

 maxilliped unguiculate; mouth a short siphon projecting ven- 

 trally. First four pairs of legs biramose, with three-segmented 

 rami; fifth legs entirely lacking but each replaced by a single 

 small seta. 



This genus belongs to the siphonostomous Cyclopoida, and 

 is distinguished from the other genera in that group by the 

 eight-segmented first antennae, the uniramose second an- 

 tennae, and the absence of fifth legs. Furthermore, the meta- 

 some is not at all depressed and is without epimeral plates. 



Genotype. Danodes plumata. 



Danodes plumata, new species 

 (Figures 57-68) 



Occurrence. Some thirty specimens, all females, were ob- 

 tained from eleven stations in the eastern and central Pacific, 

 but the species was not found in the Atlantic. Most of the 

 specimens were captured at the surface, but one was found in 

 a 50-meter tow and a few in 2 loo-meter tows. 



Description of female. Metasome pyriform and well arched 

 both dorsally and ventrally, two-thirds as wide as long. Head 

 completely fused with the first thoracic segment, the resultant 

 cephalothorax widest considerably behind its center. Free 

 thoracic segments diminishing rapidly in width backward 

 and without epimeral plates, but the fourth segment has 

 bluntly rounded processes at its posterior corners extending 

 backward and slightly overlapping the fifth segment. Uro- 

 some five-eighths as long and one-sixth as wide as the meta- 

 some, and five-segmented. The fifth thoracic segment is a 

 little more than half the width of the fourth; the anterior part 

 of the genital segment is as wide as the fifth segment, with 

 an oviduct opening on each lateral margin; the posterior part 

 is tapered to the same wicith as the first abdominal segment, 

 where it joins the latter. 



The abdomen is three-segmented, the segments diminish- 

 ing considerably in length posteriorly, but only slightly in 



