608 SHUFELDT—OSTEOLOGY OF THE WOODPECKERS,  [0cet.5, 
In Co/apftes the manubrium is strongly bifid, pneumatic foramina 
occur at all the points mentioned above, the notches of the hinder 
part of the body are profound, and the anterior border of the 
carina is convexed forward. In Campephifus the manubrium is 
small and feebly bifid, and there is no median pneumatic foramen 
posterior to its base; the articular borders of the costal processes 
are very broad transversely; the body of the bone is much ex- 
panded posteriorly, though the ‘‘ notching ’’ is comparatively shal- 
low; the anterior carinal border is irregularly scalloped. 
In the Pileated Woodpecker we find a sternum closely resembling 
the bone in Campephilus; in it, however, the notches are com- 
paratively deeper, the bifurcation of the manubrium more evident, 
and the carina comparatively deeper. This notching of the 
xiphoidal margin of the sternum though is found to vary with re- 
spect to its profundity in different individuals of the two last- 
mentioned genera. 
Dryobates has a typically picine sternum, with a bifid manu- 
briuni, and the anterior border of the carina nearly straight and 
vertical—a condition that is likewise present in the bone in Xeno- 
picus. 
Picotdes arcticus exhibits nearly the same characters with the last 
two, but in it we find a sternum that calls to mind the bone as it 
occurs in some of the Passeres. The carina is deeper and not so 
prominently brought forward in front. Four notches behind, 
however, dispel the resemblance. 
Changing pattern again in Je/anerpes torquatus, we find a ster- 
num with a shallow keel, with a conspicuously produced fore part ; 
a subaborted bifid manubrium; a shortish body, with thin costal 
processes; and, finally, the bone less pneumatic than is the rule 
among Woodpeckers. Some of these features are carried still far- 
ther in MZ. carolinus, where pneumaticity of the bone is at its 
minimum, and the bifurcations of the minute manubrium are almost 
or quite aborted. In this species, however, the xiphoidal processes 
are slender, and the notches that create them more than usually 
deep. All this agrees very well with what we find in JZ. wropygiats, 
but in the sternum of this bird the carina again is very shallow 
and the ‘‘notches’’ not strikingly deep—at least not nearly as 
much so as they are in JZ. carolinus. 
Other species of this genus show some slight individual peculi- 
arities in their sterna that, taken in connection with other charac- 
ters, ought to some day assist in determining affinities. 
