TRANSFORMATION OF ORGANS OF ANIMALS 



en 



maxillipede (fig. 10), but here it is more striking, 



and considerably modifies 



the general appearance of 



the appendage. The exopo- 



dite (ex.) is well developed, 



especially at its base ; the 



endopodite (en.) is small and 



consists of only two joints ; 



in the prodopodite (pr.) the 



FIG. 10. Aslacusfluviatilis. First 



tWO Component Segments leftmaxillipede(l,5/l):co,coxo- 



podite, and 6a, basipodite, form- 

 ing P r i protopodite ; en, endo- 

 podite ; ex, exopodite ; ep, epi- 

 podite (Huxley). 



are transformed into 

 two long thin plates, 

 and the podobranch 

 is replaced by a mem- 

 braneous plate (the 

 epipodite) (ep). Behind 

 the maxillipedes are 

 the claws and the four 

 walking legs. In these 

 five pairs of appen- 

 dages the exopodite 

 shows most signs of 

 degeneration. We will 



FIG. 11. Astacus fluviatilis. Second left 



walking lee (1,5/1) : co, coxopodite and nOW examine the CO1H- 

 ba, basipodite, forming pr, protopodite; 



fir, gill ; t, ischiopodite ; /7j,meropodite; poneilt parts 01 these 

 ca, carpopodite; p, propodite; rf, dacty- 



ite (Huxley). 



appendages (fig. 11). 

 The protopodite (pr.) consists of two parts (ba. and 

 co.), and carries a gill (br.) except in the last walking 



