new Parasitic Copepods on Fish. 89 



in length from without inwards; the first joint of the inner 

 branch has one, the second six short hairs. Hamulus very 

 small. 



Fourth jyerceopod of considerable size and robust form, con- 

 sisting of four joints, the last terminating in a minute spur, 

 close to which are placed three end-claws, two others being 

 placed at tlie inner end of the second and third joints ; each 

 of these five is seen to have a minutely crenate edge, which 

 on higiier magnification shows a beautifully serrated border, 

 transversely striated; an abortive fifth limb is found at the 

 angle of the genital segment in the form of a small tubercle, 

 giving rise to tliree short plumose hairs. 



Genital segme?it oval, with a truncated posterior border ; 

 equals half the length of the cephalotliorax. 



Abdomen elongated, as long as the last segment, con- 

 sisting of a prolonged lirst joint and a second of a square form. 



Caudal plates small, slightly longer than broad, with three 

 long terminal plumose hairs and two minute ones on the 

 outer border. 



Length 6-7 millim. 



Anueetes, Hell. 

 Anuretes perplexuSy sp. n. (PI. V. fig. 3.) 



This genus was formed by Heller, and has been retained 

 by Gerstaecker, the original specimen having been described 

 by Kroyer as Lepeophtheirus Heckelii\ it is distinguished 

 by " the entire deficiency of separate tail-segments," all other 

 parts agreeing with tlie genus Lepeophtheirus. The first 

 specimen was obtained from Ephippus gigas in the Brazilian 

 sea, described by " Roller " as Caligus Heckelii, being pre- 

 served in the Vienna Museum. A second specimen was 

 taken from the same species of fish off New Orleans by 

 Kroyer ; he states that " this species has a moderately wide 

 diffusion." I have been fortunate enough in a far removed 

 locality — namely at Trincomalee, Ceylon — to find on a species 

 of Lutjanus about a dozen specimens of a second form of this 

 peculiar animal, though the necessity for making for it a 

 distinct genus seems to me rather doubtful, for in some the 

 position of the caudal plates is as Kroyer describes, but in a 

 few these project a little beyond the posterior edge of the 

 genital segment, though in none does " the abdomen appear 

 drawn out." 



Female. — Cephalothorax rather broader than long, nar- 

 rowing in front ; the posterior lateral angles obtuse, not 



