58 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. 5.5 



4. Abdomen more than half the length of the trunk 5 



4. Abdomen short and blunt 6 



6. Posterior horn half the length of the head, lateral horns much shorter; ab- 

 domen twice the length of the trunk (45 mm.) 



louyivcntris, new species, p. G6. 



5. Posterior and lateral horns the same length; abdomen a little longer than 



the genital segment (70 mm.) procerus (Leidy), ISSS, p. G9. 



5. Posterior and lateral horns the same length as the head ; abdomen as long 

 as the genital segment (50 mm.) vorax Ilichiardi, 1S77. 



5. Posterior and lateral horns one-third the length of the head ; abdomen much 



sliorter than genital segment (70 mm.) polijnemi Bassett-Smith, 1S9S. 



6. Head subtriangular, with no lateral horns, but with a single dorsal tubercle; 



neck three times the length of the trunk; abdomen very minute (28 mm.) 



gracilis Heller, 1SG3. 

 6. Head hastate, bluntly pointed anteriorly ; two lateral and a dorsal knob ; 

 neck shorter than the trunk; abdomen of medium size (40 mm.) 



sardinac Baudouin, 1904. 



6. Head club-shaped, with lateral but no dorsal knobs; abdomen lacking, the 



trunk ending in a point (GO mm.) Icsucurii Milne Edwards, 1840. 



Eemarks. — Three species, ahdominalis ISIilne Edwards, 1840, 

 Idbracis and sargi Richiardi, 1880, ascribed to this genus have never 

 been figured, and the hist two have not even been described, so they 

 are of necessity omitted. 



Four species, infexus and nodicornis Steenstrup and Liitken, 18G1, 

 gempyli Horst, 1878, and ertstallformis Brian, 1912, are transferred 

 to the new genus Sarcotretes established by Jungersen in 1911. With 

 reference to the horns we may notice that in the genus Lernaea they 

 are always soft, while in Lernaeenicus those of the first two species 

 in the key (radlatus and pobjceraus) are as chitinous as in Ler- 

 naeocera, those of sprattae and affixus are only partially chitinized, 

 while the horns, or better, the loiobs of the remaining species are 

 usually soft. 



The two species, vorax and neglectus^ described and figured by 

 Richiardi in 1877, are probably identical. The only dilfcrence which 

 Richiardi could find in them was that neglectus averaged only two- 

 thirds the size of vorax. He himself said of the former species, 

 " It is impossible to find in its general form any characters which 

 will distinguish it from vorax. It does not differ in the form and 

 position of the antennae, the buccal apparatus, the maxillipeds, the 

 number and conformation of the segments or in the form of young 

 individuals, and hence in the progressive deformation of the testa 

 as also in the mode of attachment to the body of the host" (p. 20G). 

 In other words, we have to conclude that it does not differ at all, but 

 is the same species and hence neglectus is made a synonym of vorax. 

 In his profile view Richiardi represented the eye of vorax as actually 

 protruding from the dorsal surface of the head. 



