46 BRITISH COPEPODA. 



I do not know of its occurrence in the cavities of 

 Ascidians. 



The distinctly divided first abdominal segment of 

 the females of this species, though unmistakeably 

 observed in all which I have dissected, may very 

 probably be a sign of immaturity, none of my 

 specimens having been found with ova ; and I suspect 

 also that the undivided inner branch of the fourth foot 

 may be explicable in the same way. 



3. LICHOMOLGUS ARENICOLUS, Brady. PI. LXXXVII, 



figs. 17. 



Boeckia arenicola, Brady. Nat. Hist. Trans. Northumberland 

 and Durham, vol. iv, p 430 (1872). 



Body elongated, subpyriform; anterior antenna) 

 about half as long as the first segment of the body, 

 6-jointed (fig. 2), second joint much the longest, third 

 less than one third as long, fourth, fifth, and sixth nearly 

 equal, and about two thirds thelengthof the second joint. 

 Mandibles (fig. 3) much like those of L. liber. Last joint 

 of the first pair of foot-jaws (fig. 4) armed with six 

 nearly equal marginal spines. Last joint of the second 

 foot-jaw forming, in the male (fig. 5), a broadly ovate 

 hand, roughened with numerous denticulations, and 

 bearing a long terminal falcate claw. The fifth foot 

 (fig. 7) is in the form of a long subclavate joint, bear- 

 ing on the broad truncate apex three setse, one of which 

 is short, the other two nearly as long as the limb itself ; 



