AND CLASS IFTCATTON OF TFTE FOSSIL REFT I LEA, 
275 
their length, and extend forward and downward. I have no donbt that they are the 
VOmera. On each of these bones there were two rows of teeth. In each outer row 
there were about six ; their bases are folded like the teeth of Labyrinthodonts. 
At the back of the lateral palatal vacuities between the voinera and pterygoids is a 
pair of small oblong, obliquely placed ossifications, vdiich I regard as the palatines. 
They have been injured in excavation, but are 7 raillims. long ; their width is not 
shown. 
At the back of the palate there is a pair of rod-shaped bones, constricted in the 
shaft, truncated at the ends, which are 2 millims. wide, and with the longer 1'2 centim. 
long, which I have previously regarded as the hyoid. Their anterior ends converge 
forward, and are 1’5 centim. apart. They are shifted from the median line towards 
the left side in harmony with the shoulder girdle. 
The Shoulder Girdle of Procolophon. (Plate 9, fig. 9.) 
The bones of the shoulder girdle are very little disturbed, though the scapula is not 
exposed and the clavicle is only imperfectly preserved. But the inter-clavicle, pre¬ 
coracoid, and coracoid are exceptionally well seen, and situate immediately behind the 
back of the skull. 
The inter-clavicle is the key to the arch. Owing to its anterior convexity, the bone 
has the form of a pick-axe. It is shaped as in some Labyrinthodonts, as in Ichthyo¬ 
saurus, and many Lizards, but it has the form of a more elongated and slender capital 
T than has the bone in Monotremes. The transverse bar is about 14 millims. long, 
and the median bar is nearly 4 centims. long. The anterior margin of the median bar 
is convex, and reflected a little downward, so as to make the posterior half of the bar 
appear impressed. The limbs narrow as they extend outward, being one-half as wide 
at the termination as at their origin. The transverse measurements are 4, 3, and 
5 millims. The median staff has sub-parallel sides, being a little contracted in the 
middle, so that there is a tendency for the distal end to widen, though the widening 
is much less marked than in Monotremes. 
An elevated median ridge runs down the length of the median bar, which is other¬ 
wise flat. It unites with the transverse bar at a right angle, though the junction is 
not notched out, but rounded. 
The pre-coracoid and coracoid are in close sutural union with each other, and their 
antero-posterior length is about 2’6 centims. They are flattened, somewdiat oblong, 
moderately thin plates; but there is no evidence whether their straight inner margin 
rested upon the impressed lateral areas of the inter-clavicle, or whether that bone 
extended in front of them, as seems probable, after the manner of Monotremes and 
Ichthyosaurs. These bones appear both to contribute to the articulation for the 
humerus. 
The pre-coracoid is not completely exposed on either side, but as shown it appears 
2 N 2 
