PHYLOGE.N'Y OF THE PAL/EOGNATH^ AND NEOGNATH^. 



241 



eat. 



fig. 5. 

 C. 



t^.e 



A. — Inner view of a dissection of the wing oi Rhea mneneana, to show the remains of the expausor sceund- 

 ariorum and the ? proto-carin;ite condition of the flexor eurpi iihiaris. Note the large, fleshy inferior 

 portion eventually- inserted into the base of the 1st primary remex and the thin tendinous band which 

 runs along its free border, probably representing the i'incuJum elasticinH. 



B.— Inner view of a dissection of the wing of C'alodromas deijans. Note that the fleshy posterior portion of 

 the fle.cor carpi idnaria has become reduced to slender slips of muscle to the bases of the secondary 

 remiges, wliilst the vineulum elastieuiit has greatly increased in size to form a broad tendinous sheet. 



C. — Inner view of a dissection of the wing of Ojikthocomiis eristatus, showing another phase in the develop- 

 ment of the vinciiJum elastkum and the persistence of a strongly developed posterior belly to the flexor 

 carj)! uhiaris. Numerous intermediate stages occur amongst the Neot/natluf. 



eap.scc. = expansor secuadariorum. 

 f.c.u. = flexor carpi ulnaris : ' = anterior, " = ))osterior portion. 

 uJn. = ulnare. 

 li.e. = vineulum elasticum. 



radiale, the other fuses with the upper tendon of profundus, and also gives oflf two 

 slips which surround that tendon and, reuniting, fuse with the lower tendon of the 

 profundus. The lower part of the muscle (=profundus) gives oif two tendons, of 

 which the upper ends on the first metacarpal, while the lower runs to the base of the 

 last phalanx of the index. 



" The Jlexor metacarin ulnaris ends fleshily on the ulnare, but is prolonged beyond 

 this bone, receiving also some fibres from it to tlie metacarpal. 



"The mdio-metaearpalls veniralis .... arises from the ulna and not from the radius. 



" The total number of muscles in the hand of the Ostrich is twenty-three, allowing for 

 the absent ectejjicomJylo-uhiaris. The additional muscle is a small pronator quadratiis." 



