NO. 2063. NORTH AMERICAN PARASITIC C0PEP0D8— WILSON. 653 



antennae with a curved exopod and a jointed endopod, making the 

 rami somewhat chelate; first maxillae tripartite, palp with one or 

 two minute spines; second maxillae long and usually quite corru- 

 gated, sometimes joined at their tips and furnished with a bulla, 

 sometimes separate, with their ends enlarged in various patterns 

 and clasping a chitin bar; maxillipeds with a short terminal claw, 

 shutting against a projection on the second jomt. 



Generic characters of male. — Anterior portion of cephalothorax at 

 right angles to the posterior portion and the trunk; no distinct 

 dorsal carapace; thorax segmented with an enlarged genital segment; 

 a well-defined and segmented abdomen, carrying anal laminae. 

 First antennae indistinctly four-jointed; second antennae biramose, 

 rami usually curved and chelate; first maxilla tripartite, palp with 

 two setae; second maxillae and maxillipeds some distance behind 

 the other mouth parts and close together. 



Type. — Charopinus dalmanni (Retzius). 



{Charopinus, the name of a parasite in Martial.) 



RemarJcs. — Kr0yer's description of the species (dalmanni) which he 

 made the genus type, and of a new species ramosus, and the details 

 given in his figures, leave no doubt that the "new" genus and species, 

 StylopJiorus hippocephalus, proposed by Hesse in 1878, is really 

 only a new species of Charopinus. To these three species Scott 

 added a fourth, duhius, in 1900, but if one will examine the figures 

 and description in the same paper (1900, p. 173) of the species which 

 Scott named Lernaeopoda cluthae, it will be evident that this also 

 belongs to the present genus and not to Lernueopoda. This genus 

 is the only one in the entire family in which the adult male is com- 

 pletely segmented, while the male of Lernaeopoda shows no segmen- 

 tation whatever. In particular the partial or complete separation 

 of the two segments bearing the second maxillse and maxillipeds is 

 characteristic of the male Charopinus, and this is admirably shown 

 in Scott's figure. His species, therefore, must be removed from the 

 genus Lernaeopoda and placed here with the other species of Charopi- 

 nus. Exactly the same statements apply to the species called 

 Brachiella malleus by Nordmann (1832, p. 95) and Vogt (1877, 

 p. 46), and also to the species named below (dentatus), in each of 

 which the male proves beyond a doubt that the species belongs to 

 the genus Charopinus. It will be noted also that every species of 

 the genus as here constituted is parasitic upon the gills or in the 

 nasal openings of a ray. 



TABLE OF SPECIES. 



1 . Tips of second maxillae completely fused and furnished with a bulla for attachment 

 to their host 2. 



1. Second maxillae entirely separate or sUghtly coalesced, the tip of each enlarged and 

 anchored separately in the host 3. 



