104 Transactions. — Zoology. 



Integument very strong, smooth, opaque-brown in colour. Length, 

 -^g of an inch. Ovisac single. 



Hab. Dredged in Dunedin Harbour ; not rare, but easily overlooked 

 on account of its colour. 



Genus Thalestris, Clans. 



Body usually slender and elongated. Anterior antenna? 8- or 9-jointed ; 

 inner branch of posterior pair 2- or 3-jointed. Mandible-palp large, 2- 

 branched. Maxilla? strongly toothed, palp usually terminated by a large 

 claw. Anterior foot-jaws ending in a strong claw, and bearing several 

 setiferous marginal processes. Posterior pair forming a strong prehensile 

 hand. First pair of feet with both branches 3-jointed, and furnished at the 

 extremities with strong prehensile claws ; first joint of inner branch much 

 elongated, second and third very short; first and third joints of outer branch 

 short, middle greatly elongated. Second pair in the male have the third 

 joint of the inner branch wanting or very much reduced in size, and con- 

 verted into two or three strong spines. Fifth pair of feet 2-branched, 

 foliaceous ; much reduced in size in the males. Ovisac single. 



1. T.forficuia, Claus. PI. X., figs. 16-21. 

 (Thalestris forficula, Claus. Die frei lebenden Copepoden, p. 131, taf. xvii., figs. 7-11)- 



Body rather slender; abdomen long, narrowing very gradually, poste- 

 rior margins of the segments pectinated with rather long teeth ; rostrum 

 acute, of moderate length. Anterior antenna? 8-jointed; in the female 

 tapering gradually, and furnished with numerous seta?, the basal joint 

 about four times as broad as the apical, fourth joint bearing a long auditory 

 seta ; in the male the joints are irregularly swollen and bent. Posterior 

 antenna? rather strongly spined on the lower margin ; secondary branch 

 small, 2-jointed, and bearing 4 seta?. The posterior foot-jaws have a short 

 basal joint, and a rather stout hand, furnished with a single long seta in 

 the middle of the inner margin ; terminal claw long and slender. First 

 pair of feet with both branches long and slender ; the outer, which is much 

 the longer of the two, has the basal joints greatly elongated, and the second 

 and third very short and apparently anchylosed, the basal joint bears a single 

 rather short seta on the inner margin above the middle, while the terminal 

 joint carries two nearly straight claws of unequal length ; inner branch 

 with the middle joint very long, toothed along the outer margin, terminal 

 joint bearing four slightly curved and toothed claws. Feet of fifth pair 

 with the outer joint large and oval in the female, and extending to half the 

 length of the abdomen. Caudal forks short, and somewhat divergent. 

 Central caudal seta? nearly as long as body, swollen just beyond their basal 

 articulation, and marked along the greater part of their length with annular 

 articulations ; outer seta? about half as long as inner and lying very close to 

 it. Length, J^ of an inch. 



