No. 477] RHODE ISLAND COPEPODA 



inner border lobes. Proximal lobes of the second maxilla much 

 reduced. Maxillipeds 3-jointed. Inner ramus of first to fourth 

 swimming feet 2-jointed (or the first with 3 joints). Fifth limb 

 with one ramus in female, 2- or 3-jointe<l in the male, similar 

 to Acartia, but strong-er. 



Tortanus setacaudatus n. sp. 



Figs. 12-15 



Last thoracic segment free. First antenna long, IT-jointed, 

 reaching beyond the end of the furra by one or two joints. The 

 maxillipeds are extraordinarily larg(> and arc carried in a very' 

 characteristic manner, ?. e., horizontally and at riuiit angles to tlie 

 sagittal axis, so that the long curved, bristled, and toothed setii? 

 point forward. Abdomen and furca long. 



frmah'. -WnUnmm ;^j<)inted. slightly conipresse.l laterally. The 

 left arm of the furca is sharply coni{)ressed laterally at its base; 

 otherwise the furca and abdomen are synnnetrical. (Jenital seg- 

 ment enlarged, slightly rounded with a rounded prominence on 

 each side of the genital ()|)eiu'ng. Anal segnu>nt with an acute 

 strong dorsal spine. Kach arm of the furca is fringed with soft 

 bristles along the distal half of its inner edge, and has the full 

 number of seta'. Five of these are plumose and unjointed, and 



and' is naked and joiut.'d near 'the ba>e. The t'hird s^ta from the 

 in.side is lonovr than the majorit\ and it. projecting end bears 

 stiff, long bristles which are more scattered than the ofher>, and 

 are attach.ed at ditferent angles. Feet of the fifth pair 2-jointed, 

 alike -Fiu'. l.V. Kir.i joint ..hlon- with a })lumo.e bristle on the 



first, with h.ur short, broa.l ,>pi.ies. one near the nn-.l.lle of the 



