COPEPODS OF THE WOODS HOLE REGION 595 



106. Last metasome segment expanded laterally, eaeh pointed 



epimeral plate with a rigid seta; first antenna 6-segmented, 

 with 4 apical setae; brackish water. 



$ Microcancerilla Norman and Brady, 1909 

 Head, first 2 metasome segments, and genital segment with 

 bluntl.v rounded epimeral plates; first antenna 9-segmented, 

 densely setose 107 



107. Epimeral plate on genital segment with smooth lateral margin; 



end segment of first exopod with 3 spines and 5 setae; fifth 



leg a knob; on nudibranchs ? Artotrogus Boeck, 1859 



Epimeral plate on genital segment with deep lateral notches; 

 end segment of first exopod with 2 spines and 4 setae; fifth 

 leg a lamina; pelagic, 190 fathoms 9 Dystrogus Giesbrecht, 1899 



108. Metasome elongated, subcylindrical, partly fused; first 2 pairs 



of legs anterior and juxtaposed, third pair at center of body; 



on annelids 9 Sabellacheres M. Sars, 1861 



Metasome truncated anteriorly, scarcely longer than wide; all 



3 pairs of legs close together; fifth legs 2-segmented, with 2 



setae; gills of fishes 9 Metopocatacoteinus Hesse, 1871 



109. Urosome of female 2-segmented; fifth leg 2-segmented, basal 



segment an oblique plate, with 1 outer seta, terminal seg- 

 ment oblong, without setae; in spine of Calveria. 



9 Calverocheres, new name^' 



Urosome of female 3-segmented, of male 4-segmented 110 



Urosome of female 4-segmented, of male 5-segmented 112 



110. First endopod modified for prehension, its segments fused, 



with sucking disks; metasome with epimeral plates; gills 



of Callianassa cf 9 Clausidium Kossmann, 1875 (p. 344) 



First endopod unmodified; metasome without epimeral plates 111 



111. First exopod 2-segmented, endopod 3-segmented, both wid- 



ened; first antenna 4-segmented; second antenna 2-seg- 

 mented, with 4 apical claws; eyes of fishes. 



cf 9 Pseudoeucanthus Brian, 1906 

 Both rami of first leg 2-segmented, not widened; first antenna 

 17-segmented; second antenna 4-segmented, with apical 

 setae; freshwater cf 9 Cyclops (part) O. F. Muller, 1776 (p. 322) 



112. First exopod 3-segmented, endopod 2-segmented; first antenna 



7-segmented, its basal segment fused with head; second 

 antenna 4-segmented, with 4 apical claws; littoral, among 

 algae 9 Assecula Gurney, 1927 



Both rami of first legs 2-segmented; first antenna 4-segmented; 

 second antenna 3-segmented, tipped with 2 processes and a 

 tuft of long setae; gills of fishes 9 Phagus Wilson, 1911 



Both rami of first legs 1-segmented and much widened 113 



113. First antenna 6-segmented; second antenna 3-segmented, with 



4 apical claws and a ciliated process; fifth leg 1-segmented, 



elongate; mouth of fishes cf 9 Anchistrotos Brian, 1906 (p. 384) 



First antenna 4-segmented; second antenna 2-segmented, with 

 8 apical setae and no process; fifth leg 2-segmented, short 

 and straight; gills offish 9 Irodes Wilson, 1911 



'» Hansen established in 1902 a new genus, Echinockeres, but this name had been preoccupied by Claus 

 in 1889 for another copepod genus; compare 11 in this key. 



