REPORT ON THE COPEPODA. 93 



very stout and bent almost rectangularly ; the foot of the left side is simple, its last joint 

 hearing a few small apical setae. The fifth pair in the female are very slender (fig. 8), 

 the penultimate joint giving attachment to two slender, one-jointed branches, the inner 

 short and bearing two small apical setae, the outer about thrice as long, with one marginal 

 and four long apical setae. Abdomen of the male five-jointed (fig. 11), its third joint 

 with a large protuberance on the right side; caudal segments rather longer than broad, 

 setae five, equal. In the female there are six non-spathulate tail setae (fig. 10), the second, 

 counting from the inside, thinner than the rest and not ciliated. 



Habitat. — Off Port Jackson, Australia; between Api and Cape York; between Arrou 

 and Banda ; off Kandavu, Fiji ; off the north of Papua ; off the Philippine Islands ; and 

 off St. Vincent, Cape Verde. 



This seems to be one of the most widely distributed of the pelagic Entomostraca, 

 though seldom or never occurring in very large numbers. Prof. Dana gives a long 

 list of localities in which he found it, and I do not doubt that the form named by him 

 Pontellina turgida is referable to the male of Pontellina plumata. It is remarkable that 

 the setae of the mandibles and antennae, which, on account of their length and dense 

 ciliation, form so unique a feature in the female, are of no great length and scarcely at all 

 plumose in the male. 



** Head with lateral spines ; apex of posterior foot-jaw four-jointed. 



5. Pontella lasvidentata, n. sp. (PI. XXXVIII. figs. 1-6). 



Length, l-15th of an inch (1*6 mm.). Cephalothorax elongated, cylindrical, posterior 

 angles spinous, that of the right side doubly spined ; sides of the head produced near 

 the front into two recurved spines. Eight anterior antenna of the male (figs. 2 and 3) 

 only moderately swollen, one joint on each side of the hinge provided with a minutely 

 serrated marginal plate ; at the proximal extremity of the upper and distal extremity of 

 the lower plate is a long, adpressed, curved spine, pointing towards the apex of the 

 antenna. Swimming feet slender, with very slender terminal spines. Fifth pair of feet 

 of the male (fig. 5) one-branched, that of the right side doubly hooked, that of the left 

 terminating in three unequal, crooked spines, the longest of which (fig. 6) has a villous 

 enlargement at the base. 



Habitat. — Taken off Sibago Island, Philippines, October 23, 1874. One specimen 

 only was found, and the structure of the lower foot-jaw was not accurately noted. 



6. Pontella krbyeri, n. sp. (PI. XXXIX. figs. 1-19). 



Length, 1-1 lth of an inch (2'3 mm.). Cephalothorax robust, lateral posterior angles 

 forming stout triangular acuminated processes. Anterior antennae (fig. 2) twenty-three- 



