neio Parasitic Cop&pods on Fish. 9 



setae, the ones nearest the lunulse being the largest ; at the 

 end are three strong bristles, equalling in length the second 

 joint, ■which terminates in three or four long bristles and 

 several short ones. Posterior antennce three-jointed, the last 

 in the form of a strong hook, the basal joint carrying a sharp 

 pointed process. Hamulus very small and blunt. First 

 maxilliped having a long pointed palp at the base ; terminating 

 in a bifid claw at the end, not very long. Second maxilliped 

 with a stout basal joint, having a small spur at the base; 

 terminal hook sliortcr than the basal joint. Furcula with a 

 wide elongated base, giving off from a narrow neck two flat- 

 tened, blunt, almost straight, simple branches. First perteo- 

 pods three-jointed ; there is a small short spur at the outer 

 end of the anterior border of the second joint ; the third is 

 short and carries three short terminal bristles, the posterior 

 border being provided with three long finely plumose set£e. 

 The second perceopod has the terminal joint of the outer 

 branch furnished with eight long plumose sette, the anterior 

 border with three short simple bristles, the first joint bearing 

 two long chitinous spines. Third perteopod shows a very 

 small straight hamulus posterior. Fourth perasopod is strong, 

 terminating with four long, slightly curved claws placed close 

 together, and a fifth about halfway up the inner border. 

 Genital segment broader than long, posterior angle lobed, 

 bearing a rudimentary fifth limb, furnished with three plumose 

 hairs. Abdomen indistinctly two-jointed, almost as long as 

 the cephalothorax. Caudal plate longer than broad, with 

 three long terminal plumose setse and two shorter ones on the 

 outer side, also one on the inner border. 



The male (PI. IV. fig. 2) has a more elongated genital 

 segment, a more distinctly two-jointed abdomen^ the second 

 maxilliped is very strong, the claw being provided with a 

 small bristle near its lower third ; and on its basal joint, front 

 border, are one single and three bifid tubercles. 



Caligus {Scicenophilus^ Van Ben.) Benedeni, sp. n. 

 (PI. IV. fig. 3.) 



This species I have only taken once — a female, from 

 Scicenia diacanthus, at Bombay. 



CephalotJioracc one fifth of the whole length and much less 

 broad than the genital segment ; it is almost circular in shape, 

 bearing fairly strong frontal lobes with a straight border; 

 the lunulee are very small. Basal joints of anterior antennce 

 provided along the anterior border with about twelve very 

 tine plumose setse, the second having at its thickened end two 



