SOME PAEAS1TIC COPEPODA. 47 



the same scale as the female, is given here. The abdomen is composed of three segments 

 and the caudal furca. The first and second antennae and the mouth-parts are the same 

 as in the female. The first maxillipeds (tig. 5) are quite different ; they are very- 

 conspicuous, and serve at once to distinguish the sexes. Claus describes them [op. cit. 

 p. 377) and also the swimming-feet, the fourth pair of which differs somewhat from 

 those of the female. 

 All the specimens examined were from the nostrils of the Cod {Gadus morrhua, Linn.). 



Family Chondracanthid^:. 



Genus Chokdracanthtjs, De la Roche (1811). 



Chondracanthtjs inflatus, sp. n. (PL 9. figs. 9-15.) 



General Appearance (female). 



In appearance the female is very stout and swollen, the body being curved slightly as 

 shown in the figure (fig. 9). The head is separated from the body by a deep constriction, 

 and bears a pair of strong curved hooks, the second antennae ; these project considerably 

 beyond the ventral surface of the head, and by means of them the parasite is attached to 

 its host. There are no traces of the first antennas. The first thoracic segment is short 

 and rounded dorsally, and bears a pair of blunt bilobed appendages. The constriction 

 which separates this segment from the posterior one is less marked than the division 

 between the head and the first thoracic segment. Traces of three more segments can be 

 made out, the first of which is the shortest and bears another pair of bilobed appendages. 

 The postabdomen is very short and projects beyond the genital segment ; it is roughly 

 pyramid-shaped with a blunt apex, and shows traces of two or perhaps three segments. 

 On the last of these are a pair of small caudal furca. Just anterior to the furca are the 

 openings of the oviducts. It is doubtful whether these are true segments or only 

 secondary foldings. There are no lateral processes. Two transparent tubes run down 

 each side of the genital segment beneath the dorsal surface. On the ventral side of the 

 minute postabdomen the oviducts with narrow necks and wide ends can be seen 

 (fig. 14, Od.). They open to the exterior on the sides of the abdomen, at a point a 

 little posterior to the middle of its length. No ovisacs were present, and the ova inside 

 the body were not fully developed. A minute male was attached to the female just 

 above the abdomen on the ventral surface (fig. 9, d ). 



Appendages (female). 



First Antennae. — Not developed. 



Second Antenna. — A pair of stout hooks on a broad basal joint, very similar to these 

 appendages in other species of Chondr acanthus. 



Mouth-parts (fig. 13).— Two pair of appendages (the second maxilla? and first 

 maxillipeds) and part of a third pair (the first maxilke) are situated posterior to the 



7* 



