DIOSACCUS. 69 



LX, fig. 14). Anterior antennae slender ; in the female 

 the first four joints are unitedly three times as long 

 as the following four, and somewhat sparingly setose. 

 Posterior antennae (PL LIX, fig. 13) large, 2-jointed, 

 the joints slender and nearly equal ; a small 1-jointed 

 secondary branch springing from the middle of the 

 first joint. Mandible (fig. 14) short and stout, palp 

 short, 2-jointed. The hand of the second foot-jaw (PI. 

 LX, fig. 16) is pear-shaped, swollen towards the base, 

 and fringed along the middle of the inner margin with 

 a number of short cilia ; terminal claw 2-jointed and 

 much curved. Outer branch of the first foot (fig. 17) 

 half the length of the first joint of the inner branch. 

 Inner branch of the second foot of the male (PL LIX, 

 fig. 15) short, 2-jointed, the third joint giving place to 

 two spines and a long seta. Fifth pair of feet 2- 

 jointed; in the female (PL LX, fig. 18) the joints 

 are nearly equal in size, elongated, subquadrate, each 

 bearing five short setae, the larger of which are spine- 

 like and plumose ; in the male (PL LIX, fig. 16) the 

 joints are much reduced in length and bear fewer setae. 

 Caudal segments short, the outer tail seta about 

 one third as long as the inner. Length, - 2 - 5 -th of 

 an inch (1 mm.). 



This is an exceedingly distinct and graceful species, 

 and is in general easily recognised by its long, curved 

 antennas, and by the pyriform palm of the lower foot- 

 jaw ; it often occurs in considerable abundance. I 

 have notes of its capture in the following places : In 

 surface-net, Westport and Eoundstone Bays (abundant 

 in the last-named locality); on Laminariai, Clifden Bay ; 



