1900.] SHUFELDT—OSTEOLOGY OF THE WOODPECKERS. 585 
this free edge, which are afterward absorbed by the main bone. 
This process occurs in other parts of the skulls of Woodpeckers. 
Passing to the base of the skull, we see a number of points of 
interest in Co/apfes, and some few features that are not present in 
the general run of ordinary existing birds. ‘The basitemporal re- 
gion is smooth, broad and deep antero-posteriorly. Nothing 
especially noteworthy characterizes the large foramen magnum, 
with its relatively small condyle, nor the foramina in front of it 
upon either hand. A supraoccipital prominence is also present, 
being but fairly developed, and never pierced by foramina in the 
adult individual. 
Either tympanic bulla is cowrie shaped, showing a characteristic 
antero-posterior slit, and, according to Parker, this unique feature 
of the Woodpeckers is brought about by one of these bullz being 
formed by not only the corresponding exoccipital, but by two, or 
more often several, tympanices (usually three). ‘The basitemporal 
also enters into its formation (see Fig. r). 
A quadrate is of good size comparatively, with its orbital process 
stout and truncated at its apex. The ‘‘ mastoidal limb’’ is short, 
and the mandibular facets peculiar. Either pterygoid is noted for 
its pointed and lengthened meso-pterygoid, which, when zz sctu, 
reaches forward to the palatine spur of the same side. On the 
upper edge of a pterygoid a prominent and pointed muscular pro- 
cess is developed ; it has the same direction forward and inward as 
has the shaft of the bone. ‘This shaft is thin and much compressed, 
while the quadratal head is small and inconspicuous. When artic- 
ulated, the palatal heads do not meet mesially, or they may just 
barely touch each other. Occasionally we find in old specimens 
of Colaptes minute osseous *‘ prickles’’ at the usual sites of the 
basipterygoidal processes, and they represent aborted basiptery- 
goids. ‘They are more prominent in certain other Woodpeckers of 
our avifauna, but it is only rarely that the corresponding process is 
ever seen upon the pterygoid. It is present, though very rudimen- 
tary, in a specimen of the Pileated Woodpecker before me. 
The inferior border of the rostrum is rounded and not very thick 
transversely. It is very sharp in front, and below is usually carried 
out as a little spine. Either palatine is narrow, especially ante- 
riorly beyond the maxillo-palatine, or what is known as its pre- 
palatine portion. Distally this extremity is underlapped by the 
palatine process (of the same side) of the premaxillary. Poste- 
