THE CRUSTACEA 



fl.. 



--t. 



xr 



Fio. 23. 



Trunk-limbs of various Branchiopoda. A, seventh trunk -limb of Apus cancriformis 

 (Notostraca). B, third trunk-limb of Estheria obli'/ua (Conchostraca). C, fifth trunk-limb of 

 Branchinecta paludosa (Anostraca). D, eleventh trunk -limb of Polyartemia forcipata 

 (Anostraca). (A after Lankester ; B, C, and I) after Sars.) l>r, braiichia or bract ; /, 

 flabellum ; t, tactile process of the fifth endite in Estherin ; x, proximal exites of the Anostraca ; 

 1-6, the six endites, of which the first is the gnathobase. Between the flabellum and the 

 sixth endite in A is seen the " sub-apical lobe." Regarding the homology of the plate lettered 

 fi in C and D, see the discussion in the text. 



