

CYCLOPOIDEA. ]101 



natatories is sexual, it may be that the fact of the shorter setae of the 

 anterior antennae is also so, as this difference in these antennary setse 

 occurs in the Euchaetae. On account of our being unacquainted with 

 the sexual characteristics, we cannot lay down satisfactorily the distinc- 

 tions between this species and the following. 



The anterior antennae are about as long as the cephalothorax and 

 first two abdominal segments. The articulations are rather indistinct, 

 which makes the number of joints somewhat uncertain. 



The above may possibly be the female of the setigera; but we believe 

 not. It was not ascertained that the specimens were female. More- 

 over, the localities are rather wide apart. 



OlTHONA SETIGER. 



Antennae anticce fere corporis longitudine, late divaricate, 1 -articulator, 

 articulis 3 ultimis brevissimis, tertio quartoque prwlorigis, setis longis- 

 simis. Seta pedium biremium externa longa, nuda, tenuissimd sub- 

 clavata. Abdomen h-articulatum, segmentis submquis, setis basalibus 

 duabus, una prmlongd, alterd brevi. Styli caudales tenues, setd ex- 

 terna valde longiore quam stylus et prope basin styli insitd. 



Anterior antennae nearly as long as body, widely divaricate, seven- 

 jointed; the three apical joints quite short, third and fourth 

 very long, some of the setae longer than half the antenna. Ex- 

 ternal seta of natatories long, naked, very slender subclavate. 

 Abdomen five-jointed, segments subequal, setae of first joint very 

 unequal, one very short, the other longer than half the abdomen. 

 Caudal stylets slender, divaricate, outer seta almost twice the length 

 of stylet, and proceeding from near its base. 



Plate 76, fig. 6 a, animal, enlarged ; a', extremity of anterior an- 

 tenna, setae partly cut off; b, posterior antennae ; c, mandible (not in 

 natural position) ; d, maxilla ; e, maxilliped ; /, anterior leg. 



Collected in the Pacific, latitude 3° north, longitude 173° east, 

 south of Pitt's Island, Kingsmill Group, 4 A. m., April 28, 1841. 



Length, one-twentieth of an inch. Colour, faint ochreous; lateral 



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