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Appendices to Fotirth Annual Report 



large oval plates projecting downwards below the abdomen and forming 

 a prominent feature. In the male the fifth pair are arranged more after 

 the style of the corresponding limbs in T. Claiisii^ although differing in the 

 arrangement of the setae. Caudal segments as long as the last abdominal ; 

 inner setae nearly the length of the entire animal, outer about half that 

 length. This species was not found in any abundance, a few were taken 

 in March, at a depth of from 3 to 6 fathoms. 



Thalestris Clausii (Norman). — This stout little copepod was always got 

 when the surface of the water was more or less covered with weed, and 

 it also inhabits tidal pools. 



The anterior antennae are nine-jointed, the third and fourth joints in 

 the male being constricted and the fifth very much swollen. The female 

 antennae are very thick at the base, but gradually taper off towards the 

 apex. In the male each fifth foot has its outer branch much larger than 

 its inner, and the outer has six setae, the inner only three. In the female 

 the fifth pair of feet are short, and the branches nearly of the same 

 length ; the outer with six setae at its apex, the inner with five on the 

 outer half of its inner margin. 



The abdomen, like everything else belonging to this copepod, is stout 

 and strong, being composed of five broad segments. The caudal segments 

 are short, and the setae on them are of different lengths, the inner one 

 being as long as the abdomen, the outer only about half as long. In the 

 female they are swollen at their bases. 



Thalestris longimana (Claus). — This species was taken much more 

 frequently than the former. The cephalothorax is broad and much arched 

 dorsally, and the abdomen is much more robust than in T. mysis. 

 Anterior antennae nine-jointed. Posterior foot-jaw is exceedingly large 

 and broad, having its inner margin strongly serrated, and at the apex a 

 strong claw, altogether making a prominent powerful grasping organ. 

 First pair of feet are long and slender, each branch having one long 

 terminal claw. Fifth feet in the female are again broadened into large 

 plates, the outer distinctly oval, but the inner somewhat more rectangular, 

 both are ciliated ; in the male they are very strong and bear a number 

 of stout setae. Outer tail setae long and slender, inner fully the length of 

 the animal. 



Westwoodii nohilis (Baird). — Anterior antennae short, those of the 

 male six-jointed, of the female seven-jointed, all the joints are setiferous. 

 The second foot-jaw has a long slender terminal claw. In the first pair of 

 feet the outer branch is one-jointed, large, and ovate ; the inner branch 

 three-jointed, with a long and slender terminal claw something like that of 

 the second foot-jaw, but not so much curved. There is no great difference 

 between the fifth pair of feet in the male and in the female, except that 

 in the former they are somewhat stouter. Caudal segments are short, 

 each one bearing four setae, the longest inside, fully the length of the 

 abdomen. This copepod occurred pretty frequently in March of this year. 



Harpacticus chelifer (Miiller). — This is a small copepod with an elon- 

 gated slender body. In the male the anterior antenna is hinged be- 

 tween the fourth and fifth joints, the first two joints forming a large 

 jagged swelling terminating in a bent process, sparingly covered with setae 

 except at the base of the swelling. Fifth pair of feet composed of 

 two flattened plates, one projecting from the inner side of the other, and 

 strongly spinous. In the female the anterior antennae are longer and 

 more slender, nine-jointed, and bearing numerous long seta3. Fifth pair 

 of feet have their inner joints somewhat triangular, while their outer joints 

 are ovate ; the setae are strong and plumose. The caudal segments are ex- 

 ceedingly short, but the tail setae very long. This species is like H. flexits 



