PAEACOROPEIUM EXCAFATUM.—CHILTON. 51 



The fifth perceopod (fig. 16) is longer than the fourth, the basal joint is 

 somewhat narrower, the merus, carpus and propod longer ; the various joints bear 

 stout setae and some long hairs, but not the special groups of curved spines that 

 are present in the third and fourth. 



The first uropod (fig. 17 and 17a) has the peduncle considerably longer 

 than the rami, its lower margin being produced between them into a fiattened 

 process, which when fully developed reaches nearly halfway to the end of the 

 rami ; this is shown in side-view in figure 17 ; in figure 17a it is shown as seen 

 from above with a broadish base and the extremity forming a narrow vertical 

 knife-edge; numerous short spines are present on the upper margins of the 

 peduncle and of the rami. 



The second uropod (fig. 18) is shorter, the outer ramus shorter than the 

 inner, both rami and the peduncle bearing a few short stout spines on the upper 

 margin. 



The tJiird uropod (fig. 19) has the outer ramus about twice as long as 

 the inner, which bears a sharp spine on its inner margin and three long hairs 

 at the apex ; similar long hairs are found at the end of the outer ramus and at 

 the end of the peduncle. 



17 ^ 



19 



17a 



18 



Fig. 17. — First uropod, male (Eoto-iti specimen). 



Fig. 17a. — First uropod, female (Eoto-iti specimen). 



Fig. 18. — Second uropod, female (Roto-iti specimen). 



Fig. 19. — Third uropod and telson, female (Eoto-iti specimen). 



The telson {see fig. 19) has the posterior margin somewhat produced to 

 a blunt triangular point, a pair of spinules being situated at each side at some 

 distance from the extremity. 



The specimens from Lake Roto-iti are larger than those from Brighton 

 and Brisbane Eiver and, as stated above, they differ in a few points, e.g. in the 

 second antenna? of the male. It is possible that they may constitute a distinct 

 variety, but I have not found among them a male as fully developed as those 

 examined from the other localities, and in the meantime I consider the differences 

 as being due to immaturity. In any case the differences are slight and do not 

 seem to be of specific importance. 



