THIRD ANNUAL MEETING 



23 



Fig. 56-Wing bouesof a young Ostrich, with three free clawed digits shoxMng the 

 component parts of a bird's manus. and illustrating the similanty bet ^^en the 

 mamis of Archaeopferyx, as seen on the Berlin slab, Avith that of existiug birds. 



Fig. 57-Wing bones of Archaeopten/x with three free digits as ordinarily sho-^n 



Fig. 58- Wing bones of Arclweopteryx showing three free digits and two fused digits 



for the support of the quills. The identity of the fused metacarpals R and ^ 



being apparently established, leaves this as mucli niore likely than Fig. o7, the 



more so since digit III was too weak for the support of the wing feathers 



I, thumb; II to V, fingers; .V, metacarpal, or hand bones; R, radiu.^,, >, radiale, 



U, ulna; «, ulnars. 



Eadius 



Ulna 



)f, ulnare .... 

 i, intermedium 



c, centrale . . 



r, radiale ' if'rV— 



Carpales 1, 2, 3. 4, 5 ...... - ^/p>-*-*^ 



Metacarpalesl, 2, 3. 4, 5.. // 



I ...Forearm 



j... Carpus or wrist 



j... Metacarpals or hand 

 bones 



..Digits I. II, III. IV, V, 

 or fingers 



Fie 59— A generalized hand, such as may be found in tortoises and salamanders: for 

 comparison with the more specialized hands shown in succeeding figures, this 

 bein-' the structural plan of all, however divergent in appearance. 



