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Show 144 MR. W. P. PYCRAFT ON THE OSTEOLOGY [Feb. 20, a manner, the quadrate develops a columnar buttress of bone laterad of the outer condyle, for the articulation of the quadrato-jugal bar; and this column, in the Conopophagida?, rises upwards parallel with the shaft of the quadrate and for half its height. The outside of this column is gently hollowed to form an articular surface for the quadra to-jugal bar, the extreme proximal end of which rises gently upwards to slide along the glenoid surface prepared for it. W h e n the quadrate is seen from in front, the outer condyle, for the articulation of the mandible, has the appearance of being borne on a separate pedicle standing out obliquely and at some distance from the inner condyle, and this is especially marked in the Svnallaxine forms. Seen from its articular surface, the inner condyle will be found to be subcircular in shape and separated by a deep gorge from the outer condyle. which is oblong, sigmoidally curved, and has its long axis almost at right angles to the long axis of the skull. These features, it may be remembered, obtain also in the Euryla?mida? and Cotingida1. The Mandible. The mandible does not present any very striking characters, or points of value for systematic purposes. It is truncated posteriorly and has only a very short internal angular process, except in the Conopophagida1, where it is of moderate length. The lateral vacuity is always very small, and may be altogether wanting, as in the Pittida?, Piprida?, Philepittida?, and some Dendrocolaptinse. The symphysis is nowhere extensive except in the case of long-billed forms, such as Xiphorhynchus for example, wherein the rami rapidly approach one another to form a long, slender, curved rod flattened along its superior surface. iii. THE VERTEBRAL COLUMN. The presynsacral vertebra? are all heteroccelous and free. In their general characters the cervical vertebra? agree very closely with those of the Eurvkemida?, which I have already described. The odontoid ligament of the atlas is ossified in all the groups here dealt with. Hypapophyses arc well developed only in some Formicariina? (e.g. Batara), the Dendrocolaptina?, and Synallaxina?. As in the Eurylaemidae, the typical number of cervicals is twelve; following these are three cervico-thoracic vertebra?, i. e. those bearing free ribs which do not articulate with the sternum. The hindmost pair bear uncinate processes but have no sternal segment. In some, e.g. Synallaxis, there are only two pairs of cervico-thoracic vertebra?, the hindmost pair just referred to in such cases articulate with the sternum. But this point is of ^no systematic value, though of interest morphologically. The thoracic vertebra? are six in number and have well developed quadrangular neural spines, which may. as in Pipridse |