OF THE FAMILY CANTHOCAMPTIi)^. 89 



The joint which transforms the antenna into a grasping organ occurs 

 between the fused fourth and fifth, and the sixth segments. The latter is 

 provided anteriorly with four short tooth-like spines. 



The seventh and eighth segments are smaller than in the female, and the 

 joint between them is not so well defined. 



'2ncl Antenna. — The second antenna is fairly long. The proximal joint is 

 sub-divided, though not very distinctly. The outer ramus is small, uni- 

 articulate, expanded distally, and bears three spines. 



The distal joint of the antenna is expanded and bears three strong geni- 

 culated setse, which are serrated on the hinder edge, distally to the 

 geniculation. 



There are also three more slender setre anterior to these. 



Mandible. — The mandible is simple. The biting-edge consists of a sharp, 

 somewhat curved blade, and about fourteen minute teeth arranged in a 

 double row behind the blade. 



The palp is biarticulate with the proximal joint slightly expanded. The 

 distal joint bears four long setse terminally, and a shorter one laterally. 



. 1^^ Maxilla. — The first maxilla consists of a large terminal lobe bearing 

 three strong, somewhat curved spines. Anteriorly there are three lobes. 

 The first two are a little shorter than the main lobe and each bears four setee. 

 The third lies at the base of the most anterior of these two. It is minute 

 and bears two setpe, one long, the other short. 



^nd Maxilla. — The second maxilla ends distally in two lobes, each bearing 

 a stout curved spine and a slender seta. There is also a single seta 

 anteriorly. 



Maxilliped. — The maxilliped or first thoracic appendage is biarticulate and 

 ends in a stout recurved spine. The swollen distal joint is setose on its 

 anterior edge, the whole forming a subchelate prehensile hand. 



1^^ tnie legs. — The first true legs or second thoracic appendages are biramous, 

 each ramus consisting of three joints. The endopodite is narrow and much 

 longer than the exopodite, but its middle joint is short. 



The number of plumose setse is reduced, there being only one on the 

 proximal joint, one on the middle joint, and a spine and two plumose setse 

 terminally on the distal joint. 



In the exopodite there is only one plumose seta on the inner side, instead 

 of three as in the second, third, and fourth legs. 



There are three terminal setse, and four external spines, the last two of 

 which are slightly plumose. 



The second, third, and fourth true legs only differ from each other in the 

 relative length of the plumose setee and spines, and in the relative sizes of 

 the endopodite and exopodite. The latter is largest in the third pair of legs, 

 and the setse are longest in the fourth. 



