Abstract
The vertebral column in Chilonycteris is fused in the thoracolumbar and sacral regions. The sternum, ribs and clavicle are not unusual in appearance. The vertical process of the manubrium resembles the blade of a hatchet. There are thirteen ribs and the clavicle is one and one-fourth times as large as the sternum.
The scapula has a short spine, a coracoid process which is one-fourth the size. of the davicle, and there is a low secondary spine presento
The forelimb is somewhat unique in construction. There appears to be a partial secondary articulation of the humerus with the scapula without the humero-scapular lock mechanism usualIy involved. Due to this construction, the humerus ascribes a long oval in flight. There is a weakened articulation of the radius with the carpus so that the wrist does not lock in place upon extension of the manus. This allows movement of the wrist in more than one plane during flight.
The pelvis is relatively sturdy in construction and solidly fused to the vertebral column at sacroiliac and sacroischial joints.
The hind limb shows no unusual specializations. The femur, tibill and calcar are all the same length. Sesamoid bones are abundant in the foot and are found more often there than in the manus.
All secondary.fusions in the post-cranial skeleton (e.g., vertebral column, symphysis pubis, calcar) appear to be a function of age.