Thomson. — On Parasitic Copepoda. 367 



and two minute anal papillae on the posterior margin. Caudal 

 lamellse very small, 2-(?)jointed, with two minute setas at the 

 extremity. 



Anterior antennas not seen. Posterior pair in the form of 

 powerful hooked claws, by which the animal attaches itself to 

 its host ; these are 2- jointed, the basal joint being thick and 

 powerful, while the shorter and more curved terminal joint 

 bears a strong tooth on the middle of its inner surface, and 

 behind it two or three rugosities. 



First foot-jaws small and not very powerfully developed ; 

 the rather slender terminal joint ends in a feebly-chelate 

 manner in two claws, the larger (and outer) of which is finely 

 serrated along its outer margin. The second foot-jaws are 

 strongly developed. 



First pair of legs not seen. The second pair are very 

 small, the minute outer branch being free and obliquely 

 oblong, while the inner, which is in the form of a curved lobe, 

 is anchylosed to the horny basal joint. The third pair are 

 developed into large lamellar plates, the outer of which are 

 broadly oblong, and rounded at their extremity, and have the 

 narrower inner plates standing at right-angles against them. 

 The fourth pair are produced in the form of two elongated and 

 curved fleshy lobes, which are shorter than, and are com- 

 pletely hidden by, the lamellse of the third pair. 



Oviferous tubes rather longer than the dorsal shield, but 

 lying slightly folded within its margin. 



Length, 4-5mm. ; colour, dark-brown. 



Hah. A single (female) specimen was found by me on the 

 gills of a blue cod (Percis colias). 



This species is nearer to L. scrihce, Kroyer, in general form 

 than to any other of the many oddly-shaped sj^ecies of this 

 genus, but differs entirely from it in most of the details of its 

 sti'ucture. It is a very distinct form. 



fc> 



Genus Philichthys, Steenstrup. 

 1. Philichthys xiphice, Stp. Plate XXVIII. , fig. 1. 



I have several female specimens of this remarkable parasite, 

 which were taken from the skull of a sword-fish {Xiphias 

 gladius). Unfortunately, I do not know whether the speci- 

 men was taken near Dunedin, or from what part of the coast. 



The male of this species, according to Bergsoe, is a Ion"-, 

 narrow, C//c/oj;s-hke copepod, apparently free-swimming in its 

 habits. The female, on the other hand, lives in the bones of 

 the skull of the sword-fish, producing pit-like cavities in the 

 bone-tissue. Not only is the body very numerously seg- 

 mented, but the segments bear sac-like appendages whose 

 analogies are not easily made out. The oral proboscis — so 



