No. 477] 



RHODE ISLAND COPE POD A 



641 



Head separated from, or fused with the first thoracic se^rment; 

 fourth and fifth segments of the thorax fused (or not). Abdomen 

 of the female 4- or 3-jointed. Furca at least two and a half times 

 as long as broad, with six setae. First antenna 20- to 22-jointed. 

 Terminal section of the grasping antenna of the male usually 2- 

 jointed. The second antenna with a long outer ramus of two to 

 four joints. Outer ramus of mandible 3- or 4-i()iiited; irmer 

 ramus inconspicuously 2-jointed, its second joint curved outward 

 strongly. The first joint of the basipodite of the seeoud maxilla is 

 divided into two sections. Basipodite of the maxilliped short and 

 strong, inner ramus 4- or 5-jointed, some of its l)ristles branched. 

 The inner and outer rami of the first to fourth leg .^-jointed, 

 terminal joint of the outer ramus with two outer spines and a 

 terminal spine serrated externally. The iiuier lainus of the fiftli 

 limb of the female rudimentary or absent, outer l)ran( h 2- or 3- 

 jointed. Inner ramus of the left fifth liml) of male usually rudi- 

 mentary, rarely absent or transformeil into a i:!a^|)inu' organ; 

 outer ramus 2-jointed, occasionally reduced to a (•law->hai)ed 

 process of the basipodite. Inner ramus (»f the rii;ht fifth liml) 

 rudimentary or lacking; outer ramus 2- or iJ-jointed widi an end 

 claw. One or two egg sacs. 



The generic description must be moditied >li,ululv to admit 

 this species: the fourth and fifth thoracic seu-menf> are not fused 

 and the seventh and eiglitli segment^ of the tir<t antemia are not 



Pseudodiaptomus coronatus n. sp. 



completely fused and if thev 



tenna is 2.3-jointe(l. In other r 

 the generic description. The la^ 

 rounded posteriorly and i< naked 

 female. The fourth thora.ie -e; 



