88 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 



produced centrally into a rounded flap. Anterior antennae 

 (fig. 2) 7-jointed, their relative lengths being as follows: — 

 12 3 4 5 6 7 

 12 12 4 11 10 9 9 

 the first four being nearly double the width of the terminal 

 joints. All bear short spines, a long one terminating the 

 fourth and fifth joints, and three the apical joint. 



Posterior antennae (fig. 4) 5-jointed, the fourth joint 

 very short. A sharp powerful curved claw with broad 

 base forms the apex. Mandible (fig. 5) broad at the 

 base w 7 ith long slender finely setose stile t ; no palp. 

 Maxilla (fig. 6) consists of a broad base terminated by 

 two spines. 



Anterior foot jaw (fig. 7) of similar character to the 

 mandible, with one finely plumose seta. Posterior foot 

 jaw (fig. 8) consists of a single broad plate, its length 

 half its breadth, and bearing a row of fine spines on its 

 outer edge. Each branch of first four pairs of swimming 

 feet (figs. 9 and 10) 2-jointed with strong spines and 

 densely plumose setae. 



The first foot (fig. 9) is fringed with short setae on the 

 lower surface of basal joint. Fifth feet (fig. 1) 1 -jointed, 

 each having two terminal spines. 



A single specimen of this singular species (sex, male) 

 was taken by tow-net in Puget Sound.* Though bearing 

 a strong resemblance to LicJwmoIgus, its remarkable 

 rostrum and singular posterior foot jaw, as well as the 

 2-jointed swimming feet, completely separate it from that 

 genus. 



* The specific name columbice refers to its occurrence in the strait between 

 '•'Columbia" and British Columbia, and where, moreover, much good work 

 has been done by zoological expeditions from the Columbia University, New 

 York. 



