ART. 6. NORTH AMERICAN PARASITIC COPEPODS WILSON. 51 



LERNANTHROPUS PAENULATUS, new species. 



Plate 6, figs. 41-48 ; plate 7, figs. 49-50, and 56. 



Host and record of sfecimens. — Two females with egg strings 

 were taken from the gills of the amber jack, Seriola lalandi, at 

 Woods Hole, by Vinal N. Edwards. These have been given Cat. 

 No. 54057, U.S.N.M., and become paratypes of the new species. A 

 female with egg strings and a male were obtained from the same 

 host September 11, 1901, by Dr. M. T. Thompson at Woods Hole. 

 The female is made the type of the species with Cat. No. 54058, 

 U.S.N.M. The male becomes an arsenotype with Cat. No. 54059, 

 U.S.N.M. Another male was taken from the gills of the same host 

 by Dr. Edwin Linton at Beaufort, North Carolina, September 23, 

 1902, and has been given Cat. No. 54060, U.S.N.M. 



Specific characters of female. — General form elongate and nar- 

 row ; cephalothorax a little longer than wide, with large lateral flaps 

 which entirely cover and conceal the second antennae and mouth 

 tube except in a ventral view. Anterior portion of dorsal plate twice 

 as long as wide, with nearly straight lateral margins, the distance 

 between the second and third swimming legs being exceptionally 

 large. Posterior portion much widened, especially at the posterior 

 margin, and wrapped around the fourth legs and egg strings, leav- 

 ing only the tips of the fourth legs visible. Genital segment small, 

 with strongly convex sides; abdomen minute, one- jointed; anal 

 laminae narrow lanceolate, as long as the abdomen and genital seg- 

 ment together, but entirely concealed by the dorsal plate. 



First antennae six- jointed, tapering, the setae scattered except on 

 the terminal joint; second antennae with the usual swollen basal 

 joint and stout terminal claw, attached close to the anterior margin 

 of the head and covered by the side lappets of the cephalothorax. 



Mouth tube conical, rather long and narrow; first maxillae tri- 

 angular, the tip armed with two spines, the outer one much longer 

 than the inner; there is also a short but stout spine on the inner 

 margin one-third of the length from the base. Second maxillae 

 with a long and rather slender terminal claw; maxillipeds stout, 

 the claw strongly curved. 



Exopod of first swimming legs flattened, squarely truncated and 

 tipped with five short and blunt teeth; endopod of the usual form, 

 conical and tipped with a large spine. Exopod of second legs 

 somewhat boot-shaped, the " heel " on the outer margin at the base, 

 the " toe " armed witli four small spines. Endopod like that of the 

 first legs. No secondary spine inside of the endopod. 



Third legs opposite the center of the dorsal plate, turned ven- 

 trally at right angles to the body axis, not very long and not wide 

 enough to meet on the midline, even at the base, but leaving a con- 



