pointed out, differed in no essential from that of the typical 
avian wing. In some points, however, it has changed con- 
spicuously. For the bones have become greatly flattened, 
and the several parts of the wing—arm, forearm, and hand— 
can no longer be bent upon one another in the Z-shaped 
fashion of normal wings, while the “quill”? or “ flight- 
feathers” have been reduced to so small a size that they are 
unrecognizable. 
268 
