Evolution by atrophy in biology and sociology / by Jean Demoor, Jean Massart, Émile Vandervelde ; translated by Mrs. Chalmers Mitchell.

  • Demoor, J. (Jean), 1867-1941.
Date:
1899
Catalogue details

Licence: Public Domain Mark

Credit: Evolution by atrophy in biology and sociology / by Jean Demoor, Jean Massart, Émile Vandervelde ; translated by Mrs. Chalmers Mitchell. Source: Wellcome Collection.

    53/342 (page 37)
    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 endopoditc (en.) is small and consists of only two joints ; in the prodopodite (pr.) the „ 1 vr ' Fig. 10.—Astaeusfluviatihs. First two component segments leftmaxiiiipedca.s/i):™ coxo- L ° podite, and 6a, basipodite, form- n big pr, protopodite ; en, endo- .ca 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.—Astaeus fluviatilis. Second left . walking lee (1,5/1): eo, coxopodite and HOW examine the COlll- ba, basipodite, forming pr, protopodite; br, gill; is, ischiopodite ; me, meropodite; poildlt parts 01 these ea, carpopodite; p, propodite; da, dacty- lopodite (Huxiey). appendages (fig. 11). The, protopodite (pr.) consists of two parts (ba. and co.), and carries a gill (br.) except in the last walking