982 SHUFELDT—OSTEOLOGY OF THE WOODPECKERS.  [Oct. 5, 
Turning to the skull of a nestling Co/aptes, we are to note that 
the frontal processes of the bone under consideration slope gradu- 
ally up on to the frontal region about equally as far as does a nasal 
on either hand. This cranio-facial region is likewise s/ofzmg in 
the adult, though further on we shall see that it is quite different in 
some other Woodpeckers. 
Laterally, the maxillary process of the premaxillary outerlaps the 
corresponding maxillary, so that in the adult, after fusion takes’ 
place, the two bones are indistinguishably united, and no suture 
or process thereafter marks the line of union. At the roof of the 
mouth, the palatine processes of the premaxillary behave in a simi- 
lar manner ; the prepalatine extremity being the bone that outer- 
laps the backward-projecting process of the premaxillary upon 
either side. The apex of the premaxillary in all Prczd@ is gen- 
erally a little truncated off and squarely across. 
Mesially, the premaxillary unites to some extent below with the 
nasal septum, as we so often see it in other birds wherein that par- 
tition exists. 
Nothing of especial import characterizes the frontal and parietal 
bones in the ‘cranium of a nestling Colapées. Essentially they 
agree with the corresponding bones in the immature specimen of 
any ordinary passerine bird—a large Thrush, for example—where 
the external superfices of the cranial vault is smooth and rounded. 
Owing to the relatively small squamosal, however, they in 
Colaptes descend far down laterally, and this feature can easily be 
guessed at from a glance at any skull of an adult Woodpecker, 
where it will be noticed that the lateral processes of the cranium 
are comparatively near down toward the quadrate. 
The frontals and parietals of an adult Co/aptes do, however, pos- 
sess characters not yet evident in the skull of the nestling of any 
of that genus. In the first place, there is the denting of nearly the 
entire external surface of these parial bones, which is caused by 
_ the apices of the quill-butts of the capital feathers. Again, we 
note in this region, in the adult, the double impressed groove, 
leading from the supraoccipital prominence by a gentle curve to 
the posterior periphery of the right narial aperture. This double 
gutter lodges, as we know, the free ends of the hyoidean apparatus 
during the life of the individual. Adult Co/apfes also exhibit a 
slight tilting up of the postero-superior orbital peripheries, the 
margins being sharpened and a few perforating foramina occurring 
