114 ME. THOMAS SCOTT ON THE 



G-enus Mtzopontius, Giesbrecht, 1895. 



Mtzopontius pungens, Gieshrecht. (Pi. 9. figs. 1-10.) 



1895. Myzopontius imngens, (jieshrecht (53), p. 182. 



Description of the female. — Thorax broadly ovate, being about 

 one-tLird longer than broad ; the abdomen is narrow and fully 

 half the length of the thorax ; " thoracic segments scarcely 

 produced into lateral processes, neither are the abdominal " 

 (fig. 1). Antennules short, 12-jointed ; the terminal joint is 

 elongate, being fully twice the length of the penultimate one 

 and bearing an asthetask near the distal end (fig. 2); the 

 formula shows approximately the proportional lengths of all the 

 joints : — 



Proportional lengths of the joints 13 . 12 . 6 . 6 . 5 . 5 . 9 . 6 . 8 . 8 ■ 11 . 25 

 Numbers of the joints 1 2 3 4 5 6 7 8 9 10 11 12. 



Antennae (PI. 9. fig. 3) 4-jointed; third joint short, secondary 

 branch very small. Mandibles (Pi. 9. fig. 4) in the form of 

 long, slender stylets. Maxillae (fig. 5) furnished with two 

 lobes : inner short, oval, and bearing one long and one short 

 apical seta ; outer lobe elongate and narrow, and provided with 

 two apical setse of moderate length. The anterior foot-jaws 

 (fig. 6) are armed with very long and curved terminal claws. 

 The posterior foot-jaws are long and slender (fig. 7) ; the second 

 joint is elongate, but the last three are shorter and narrower, 

 and the terminal claw is moderately stout and about equal in 

 length to the last three joints. The first four pairs of swimming- 

 feet are somewhat similar in structure, and have both branches 

 3-jointed ; in the first pair (fig. 8) the end-joints of the outer 

 branches are armed with three spines and five plumose setae ; 

 the end-joints of the inner branches have one plumose seta on 

 the outer margin, three on the inner margin, and two at the 

 apex, while the second joints are furnished with two setae, and 

 the first joints with one on the inner margin. The end-joints of 

 the outer branches of the fourth pair (fig. 9) are furnished with 

 four spines and five setse ; the number of setae on the inner 

 branches is similar to that on the inner branches of the first pair, 

 except that there are only two setae on the inner margin of the 

 end-joint, and the inner one of the apical setae is replaced by a 

 slender sabre-like spine. Fifth pair (fig. 10) small, 1-jointed, 



