N0TODELPHYS. 131 



than twice as long as the preceding segment, and the 

 lateral seta is placed on the middle of the external 

 margin (fig. 9). Both branches of the fifth pair of 

 feet (fig. 10) are very mnch smaller than in either 

 of the foregoing species and much more slenderly 

 spined. Length of female y^-tk — -§-tk of an inck 

 (2 — 3 mm.), of male y^-th of an inck (3 mm.). 



N. agilis kas occurred in Ascidians taken off tke 

 coasts of Durkam and Yorkshire, in depths of from 

 twenty to thirty fathoms, and among specimens from 

 the branchial sac of Asciclia sordida, Shetland, sent to 

 me by the Eev. A. M. Norman. 



4. Notopelphys prasina, Thorell. PL XXX, figs. 



11—15. 



Notodelphys prasnia, Thorell. Loc. cit., p. 41, tab. v, fig. 7 (1859). 



The caudal segments (fig. 15) are in this species 

 much shorter and stouter than in any other, their 

 length being not more than equal to the breadth. 

 The two principal tail setse, more especially the inner 

 one, are very broad. The branches of the fifth pair 

 of feet (fig. 14) are very small, the outer about thrice 

 as long as broad, the inner about as broad as long. 

 Length of female yfth of an inck (2*3 mm.). 



Tkis species was more abundant tkan any otker in 

 a collection of Entomostraca taken from tke branckial 

 sacs of Ascidia mentula at Oban by tke Rev. A. M. 

 Norman, to wkom I am muck indebted for the 



