NO. 2063. NORTH AMERICAN PARASITIC C0PEP0D8— WILSON. 631 



it is much infested with parasitic Vorticellidae and algae, and speci- 

 mens are often found completely covered with these plants and 

 animals. 



Genus LERNAEOPODA Blainville. 



Generic characters of female. — Cephalothorax more or less inclined 

 to the trunk axis, short, thickset, and covered with a distinct dorsal 

 carapace; first one or two thorax segments well differentiated, the 

 others thoroughly fused with one another and with the abdomen; 

 no anal laminae; genital process minate; a posterior process on 

 either side of the genital process and ventral to the egg strings. 

 First antennae four-jointed; exopod of second antenna much smaller 

 than the endopod and two-jointed; mandibles slender, teeth bluntly 

 rounded or even truncated; fij'st maxillae tipped with three setae, 

 sometimes jointed; palp present, with thi-ee termmal setae; tips of 

 the second maxillae enlarged into disks or furnished with a bulla; 

 egg strmgs long and slender. 



Generic cMracters of male. — Size unusually large (2 to 3.5 mm.); 

 cephalothorax more or less inclined to the trunk axis, separated 

 from the trunk by a well-defined groove and covered with a dorsal 

 carapace; trunk of young males conical and segmented, later be- 

 coming inflated and losmg its segmentation; anal laminae often 

 exceptionally large and turned forward dorsally. First antennae 

 four-jointed; second antennae chelate; second maxillae with a large 

 spinous process on the basal joint, forming a chela with the ter- 

 minal claw; maxiUipeds much larger and stouter than the maxillae. 



Type. — Lernaeopoda hrongniartii Blainville. 



(Lernaeopoda, Aspvdioc, Lernaean and tiooc, foot) . 



Remarl's. — ^This genus was founded by Blainville in 1822, with the 

 type-species L. hrongniartii, specimens of which he observed ''in the 

 collection of Brongniart, who did not know where or on what kind 

 of a fish they had been obtained" (p. 442). He also included with 

 the type the species salmonea of Gissler, of which, however, he said 

 that he had never seen a specimen, and that possibly it did not 

 belong to this genus. An exammation of the two species quickly 

 convinces one that they belong to different genera, as here indi- 

 cated. Although Blainville's type has never been seen by any other 

 observer, it was described and figured well enough to show its rela- 

 tionship to Grant's species, elongata, and Ki'^^'cr's species, galei. 

 These two species are very well known, and have been repeatedly 

 described and figured; taken together, therefore, they will serve as 

 a sort of common coenotype of the genus, and wiU illustrate for us 

 its chief characters. 



With these three species we may retain in the original genus 

 Thomson's musteli, Kane's hidiscalis, and Richiardi's scyllii, making 



