122 BRITISH PARASITIC COPEPODA. 



segment very long and narrowly cylindrical. Its 

 distal end, in dorsal view, distinctly truncated, and in 

 lateral view broadly rounded and somewhat gibbous 

 (PL LXX, fig. 10). Abdomen short and narrow, joining 

 the ventral surface of the distal end of the genital 

 segment ; uniarticulated, but in some specimens two 

 slight constrictions appear which may correspond to 

 the distinct segments seen in the male. Furcal joints 

 moderately long and narrow, and about four times 

 longer than broad. Egg-strings short and cylindrical, 

 containing only a single row of eggs. 



Antennules short and seven-jointed; moderately 

 setif erous. Basal joint nearly as long as the combined 

 lengths of the next five, and its distal end crossed by 

 three indistinct lines as shown in the drawing (fig. 2). 

 Distal end of the last joint provided with a short, but 

 stout, sensory filament. Antennas short and stout, 

 and armed with powerful chelas which are used for 

 securing the parasite to its host, and are easily visible 

 in the entire animal, even without dissection and by 

 using an ordinary hand magnifier. 



Mandibles stylet-shaped, with the distal end of the 

 inner margin serrate as in Eudactylina. Maxillas 

 bilobed, very small and somewhat rudimentary. The 

 distal end of each lobe furnished with two setse. 



First maxillipecls small and cheliform, the claw-like 

 end joint moderately broad and spoon-shaped ; the 

 distal end of the upper margin of the joint over which 

 the claw folds slightly serrate and ciliated (fig. 6). 

 Second maxillipecls large, and forming powerful pre- 

 hensile organs, their terminal claw strongly curved 

 and nearly as long as the joint from which it springs. 



The four pairs of thoracic legs all somewhat similar 

 in structure. They are biramose, and the rami are 

 three-jointed as shown by figs. 8 and 9 on PL LXX. 

 Basal plate of the first pair produced at its distal 

 angles into minute tubercles, but in that of the second, 

 third, and fourth pairs the angles are produced into 

 moderately long and stout spines which are quite pro- 



