124 GEOLOGICAL SURVEY OF THE TERRITORIES. 
dinal canal between the two bones. The head of the coracoid rears 
well above the glenoid cavity, in order to afford the required surface 
upon its mesial aspect for the broad clavicular extremity that rests — 
against it; upon its opposite side it offers the usual surface to assist in 
completing the cavity for head of humerus. The shaft of the bone is 
very slender and cylindrical for its major part, and the wing-like exten- 
sion, so broad in many birds, is here but a meager osseous scale attached 
to the side of the shaft, for its outer and lower half, becoming continuous 
with the formal dilatation of the bone below; for the sternal articulation, 
this is transversely concave and very narrow. 
The minute pneumatic perforations of the scapule and coracoids oc- 
cupy their usual sites back of the glenoid cavity, under the protection 
of the tendinal canal, at the heads of the bones. The united clavicles, 
or the furculwm, inclines decidedly to the U-shaped variety (Figs. 94, 
95); we have already alluded to the fact as how broad, yet compressed, 
their scapular ends are found to be; from these heads the shaft-like 
portions fall downward, with a gentle carve backward to meet and sup- 
port the mesial and usual clavicular lamina, which here lies in that re- 
cess formed by the anterior and concave border of the carina of the 
sternum (Fig. 100). 
Directing our attention again to the shoulder-joint we discover that 
this Shrike is another example of those birds in which that little peg- 
like ossicle, the os humero-scapulare is found, here attached by its usual 
ligaments to the upper and back part of the articulation and fulfilling 
its ordinary function. The humerus of Lanius bears the closest resem- 
blance to that bone as found in many of the family Turdide—particu- 
larly does this apply to Mimus polyglottus, a bird the Shrike not un- 
successfully apes in point of external] coloration. 
The head, in most individuals, is well bent, anconal, and supports a 
short radial and not lofty crest, with the usual ulnar tuberosity over- 
hanging an ample pneumatic fossa. The shaft is quite straight and 
nearly cylindrical, its distal and expanded extremity presenting quite a 
unique appearance (Figs. 96 and 97). The internal and external con- 
dyles are distinct processes, the former projecting almost directly back- 
wards, the latter forwards and upwards; the olecranon fossa is likewise 
clearly defined, and on the palmar aspect we observe the oblique and 
ulnar facets unusually prominent. The humerus is the only bone of the 
pectoral limb that has air admitted to its interior, the bones of the anti- 
brachium and pinion lacking this rather rare prerogative. 
The ulna is more than four times the bulk of the radius, being, as in 
most vertebrates, the main support of the forearm; there is scarcely any 
perceptible curvature along its well-balanced and cylindrical shaft,which 
presents a row of distinct little tubercles for the bases of the quills of the 
secondaries. Its proximal end presents for examination a prominent 
olecranon process, directed backwards, and the greater and lesser sig- 
moid cavities on its anconal aspect; the distal extremity is rather under 
the average in point of eminence, but shuws all the usual indentations 
and surfaces to accommodate this end of the bone to the wrist and radius. 
The radius differs principally in having a general curvature distributed 
along its subtrihedral shaft, rather than having it confined to its proximal 
third, as in many birds; otherwise it presents its ordinary ornithic char- 
acteristics. 
Among the mature birds representing the Lantide, as in so many 
other families, the carpus is composed of the two free ossicles, the cwnei- 
Jorm and the scapho-lunar, which are here impressed by their usual ar- 
ticulating facettes, for the radial and ulna trochlee and the metacarpus, 
