cxp-- 



PlG. Yl.Astacns flnviatilis.K, one of the podobranchiae from the 

 outer side ; B, the same from the inner side ; C, one of the arthro- 

 branchise ; D, a part of one of the coxopoditic setae ; E, extremity of 

 the same seta ; F, extremity of a seta from the base of the podo- 

 branchia ; G, hooked seta of the lamina ; (A C, x 3 ; D G, highly 

 magnified). Z>, base of podobranchia ; cs, coxopoditic seise ; cxp, 

 coxopodite ; Z, lamina, pi. plume, and st, stem of podobranchia 

 t, tubercle on the coxopodite, to which the setse are attached. 



