Copepoda taken in the West of Ireland. 135 



Genus Scutellidium, Claus. 

 Scutellidium tisboides, Claus. 



Two specimens taken on weeds in a rock-pool in Clifden 

 Bay. 



Genus Thalestkis, Claus. 

 1. Thalestris harpactoides, Claus. 



Taken in the surface-net : Roundstone Bay, Ventry Bay, 

 Killybegs. 



2. Thalestris mysis, Claus. 



In the surface-net, Westport and Roundstone, and on the 

 fronds of Laminarice at Clifden. 



3. Thalestris helgolandica, Claus. 



On the fronds of Laminarim, Clifden Bay. 



The fifth feet and gnathopods of our specimens differ slightly 

 from the figures given by Dr. Claus ; and the body and an- 

 tennas of the animal, especially in the male, are beautifully 

 banded with dark vinous red. 



4. Thalestris hibemica, n. sp. PI. VIII. figs. 17-19. 



Body slender, rostrum of considerable length. Anterior 

 antennas nine-jointed, of moderate length, rather thickly clothed 

 along the anterior margin with shortish hairs ; second, third, 

 and fourth joints nearly equal in length, about twice as 

 long as broad; fifth, sixth, seventh, and ninth also nearly 

 equal, and about half the length of the foregoing ; penultimate 

 joint much smaller : anterior antennae of the male shorter and 

 swollen, third joint very short and constricted, fourth much 

 the longest and as wide as the two basal joints, armed with a 

 long falciform appendage, fifth and sixth joints about half the 

 length and breadth of the fourth, seventh and eighth very 

 small, last joint as long as the fifth, but very narrow ; a few 

 crowded setas on the margin of the second joint, and three 

 small ones at the apex of the last joint : posterior antennas and 

 mouth-organs as usual in the genus. Posterior maxillipeds 

 terminating in a slender clawed hand, in shape approaching 

 that of T. longimana, the propodos being irregularly angular 

 and subcrescentic, with the internal angle slightly setose ; the 

 unguis strong and well curved. First pair of swimming-feet 

 almost as in T. longimana, except that the terminal claws and 

 setas are longer and more slender, the two branches being 

 nearly equal, and the long claw equal in length to the branch 

 itself. The inner branch of the second pair of feet in the 



