ISOPODS OF NORTH AMERICA. 



445 



h'ui. 500.— Stenetrium stebbingi. a, Third pleopod of male, x 



41. 1), FlR.ST PLEOPOD of male. X 77^. r, SECOND PLEOPOD OF 

 .MALE. X 77i. 



two followino- joints narrow; the Hugvllnni is coniposod of nin<> joints 



jiud rraciies a little t)eyond the middle of the fourtli peduncuhir joint 



of the second paii' of antenna'. 



The second pair of antenna' iiave the first four joints short, the 



third joint being provided witli an exo])od, the tifth and sixth joints 



long and of equal leng-th; tlie llayelluni is niulti-aiticulate. 

 The first thoracic segment has the lateral margins sti-aight. the ante- 



rioi- angles acutely 



produced forward. 



Tlie lateral margins 



of the second, third. 



and fourth segment 



are also straight . wit h 



the epimera evident 



about the middle. 

 The fifth and sixth 



segments have the 



posterior half of 



the lateral margin 



rounded, the epimera 



evident below. The 



seventh segment has the lateral margin acutely produced posteriorly, 



the epimera evident on the posterior margin of the segment within 



the processes. The thoracic segments are all widely separated from 



each other by deep lateral incisions. 



The terminal segment of the body has the lateral mai'gin produced 



backward in two small spines, between which the posterior margin 



is widely rounded. The 

 iiro]M)da are double 

 bi-anched. the branches 

 being nearly (Mjual in 

 length and about as long 

 as the basal joint. 



The first piiir of legs 

 are subcludate. In the 

 male the carpus is pos- 

 tvvi) - distally ])roduced 

 in a markedly long pro- 

 cess, which extends half 



the length of the propodus, its entire margin being fringed with 



long hairs. The propodus is elongate, its lower two-thirds ))eing 



fringed with long hairs on the posterior margin, the upper third or 



distal margin being provided with three large .^^pines, the inner one 



l)eing ))ifurcate; the dactylus is long and also fi'inged with iiairs upon 



its inner margin, and extends half its length beyond the last iligital 



Fk;. .501.— Stenetrium stebbingi. «, ForRTii pleoimid ok 

 .MALE. X 41. 6, Fifth pleopod of male, x 41. r. Fikst 



PLEOPOD OF FE.MALE. X Tlh. 



