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1900. ] SHUFELDT—OSTEOLOGY OF THE WOODPECKERS. 595 
With respect to the palatines, they are interesting from the 
fact that the palatine spurs curve toward eacli other and the 
median line ; but more than this, for when either of them passes the 
interpalatine spine of its own side it presents a shoulder for the 
apex of the latter to fit upon, while after this the palatine spur is 
continued forward as a delicate osseus spine for a short distance. 
There appears to be no vomer present in Sfhyrapicus, and the 
maxillo-palatine are more than ordinarily reduced in size, while 
the great comparative breadth of this part of the skull takes them 
away still further from the prepaiatine on either side. 
As is well known, the hyoidean arches in this genus of Wood- 
peckers, although morphologically like others of the suborder, 
they nevertheless exhibit the notable feature in not having the 
thyro-hyals curve back over the cranium any more than they are 
seen to do in ordinary passerine birds. 
The mandible is as in other Pez, with its symphysis rather deep 
and the posterior angular processes slightly more conspicuous. The 
ramal vacuity is entirely absent. 
Quite a gap must exist between Colaptes mexicanus and sucha 
form as Picotdes arcticus—that is, if we be guided by what their 
skulls seem to indicate. In Prcotdes we meet with a skull that is 
possessed of a relatively very large cranial casket, globular and 
every way elegant in the extreme. It is uniformly and handsomely 
dented all over by the quill-butts of the capital feathers and is dis- 
tinctly grooved for the thyro-hyals of the hyoid as far forward as 
the cranio-facial hinge. The frontals and nasals conspicuously roll 
over the premaxalline base, but the line here is not directly trans- 
verse, as it makes an obtuse angle, with its aperture looking forward. 
The superior osseus mandible is very wide at the base, straight, 
vertically much compressed, causing the slit-like external narial 
apertures. These latter have their superior margins slightly tilted 
upward, as though the flattening of this mandible was becoming 
too great, and the nostril had made an effort later to enlarge its 
aperture.?* 
1 Some meaning, too, must be attached to the peculiar way the frontal region bulges 
over the base of the premaxillary; possibly the continual hammering these birds 
indulge in to obtain their food may have in time produced this condition. At any 
rate it has the appearance as though the premaxillary had been pushed into the 
fore part of the skull. I have noticed, too, that it is in the skulls of the most in- 
veterate hammerers that this feature is best developed. It is scarcely noticed at 
all in Colaptes, indeed it is quite absent there. 
