ART. 5. NORTH AMERICAN PARASITIC COPEPODS WILSON. 31 



Le7-nanthropus Steenstrup and Lutken, Kong. Danske Videns. Selsk. 



Skrifter, ser. 5, vol, 5, 1861, p. 395. 

 Lernanthropus Kb0yeb, Naturhistorisk Tidsskrift, ser, 3, vol. 2, 1863, 



p. 193. 

 Lernanthropus Nokdmann, Bull. Soc. Imp. des Nat. Moscou, vol. 37, 1864, 



p. 499. 

 Stalagmns Nokdmann, Bull. Soc. Imp. des Nat. Moscou, vol. 1864, p. 510. 

 Lei-nanthropus Hellek, Reise der Novara, 1865, p. 221. 



Lernanthropus Heider, Arbeit. Zoolog. Inst. Wien, vol. 2, pt. 3, 1879, p. 269. 

 Lernanthropus Goggio, Attl Soc. Toscani Scl. Nat. Pisa, vol. 22, 1906, 



p. 134. 

 Lernanthropus Brian, Copepodi parassiti del Pesci d'ltalia, 1906, p. 63. 

 Lernanthropus T. and A. Scott, British Parasitic Copepoda, 1912, p. 110. 



External generic characters of female. — Head fused with first 

 thorax segment, the resulting cephalothorax oblong or pyriform, 

 with a dorsal carapace whose lateral margins are curved over ven- 

 trally. Free thorax segments fused and covered with a dorsal plate, 

 which is prolonged backwards over the genital segment and abdomen. 

 The latter small and one-jointed. First antennae filiform, the joints 

 more or less fused. Second antennae prehensile, uncinate. Man- 

 dibles stylet-shaped, toothed on the inner markin. First maxillae 

 palp like; second maxillae and maxillipeds prehensile, uncinate. 

 First two pairs of swimming legs rudimentary, biramose, the rami 

 one-jointed; rami of third and fourth pairs transformed into broad 

 lamellae. Each lamella of the third pair represents a fused exopod 

 and endopod, projects at right angles or diagonally from the ventral 

 surface and is folded along its midline, so that its cross-section is 

 in the form of a half circle. There are usually four lamellae in the 

 fourth legs, and they extend backward. Egg strings elongate, eggs 

 uniseriate and strongly flattened. 



External generic characters of male. — Cephalothorax separated 

 from the free thorax and covered with a carapace whose lateral 

 margins are flat. Free thorax fused with the genital segment and 

 without a dorsal plate. Abdomen one- jointed and wholly visible in 

 dorsal view. Second antennae prehensile and relatively larger than 

 in the female. Third and fourth swimming legs, with the rami trans- 

 formed into thread-like filaments. 



Intemial generic characters. — The usual digestive canal running 

 straight through the entire body. Sex organs paired, the ovaries 

 lying over the digestive canal in the second thorax segment, the 

 testes similarly placed in the posterior part of the cephalothorax; 

 sex ducts much convoluted. Cement glands club shaped, extending 

 along the lateral margins of the dorsal surface and reaching forward 

 to the posterior end of the ovaries. Semen receptacle also club 

 shaped under the intestine at the posterior end of the genital seg- 



