144 ME. W. r. PYCRAFT OX THE OSTEOLOGY [Feb. 20. 



a manner, the quadiute 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 upwai'ds 

 parallel with the shaft of the quadrate and for half its heiglit. 

 The outside of this column is gently hollowed to form an ai'ticulai' 

 surface for the quadrato-jugal bar, the extreme proximal end of 

 which rises gently upwards to slide along the glenoid surface 

 prepared for it. When the quadrate is seen from in front, the 

 outer condyle, for the articulation of the mandible, has the 

 appeaiance 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 Synallaxine 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 

 light angles to the long axis of the skull. These features, it may 

 be remembered, obtain also in the Euryla-mida? and Cotingidfe. 



The Jlandible. 



The mandible does not present any very striking characters, or 

 points of value for systematic pui-poses. 



It is truncated posteriorly and has only a very short internal 

 angular process, except in the Conopophagida^, where it is of 

 moderate length. The lateral vacuity is always very small, and 

 may be altogether wanting, as in the Pittidpe, Piprida^, Philepittida^, 

 and some Dendrocolnptin^e. The symphysis is nowhere extensive 

 except in the case of long-billed forms, such as Xij^horhynchus for 

 example, wherein the rami rapidly approach one another to form 

 a long, slender, curved rod flattened along its superior surface. 



iii. The Vertebral Columx. 



The presynsacral vertebrae ai'e all hetei'ocoelous and free. 



In their general chai-actei'S the cervical ^-ertebi'te agi-ee very 

 closely with those of the Eurylfemidfe, which I have already 

 described. 



The odontoid ligament of the atlas is ossified in all the gi^oups 

 here dealt with. Hypapophyses are well developed only in some 

 Formicariinje (e.g. Batara), the Dendrocolaptina-, and )Synallaxina^. 

 As in the Euryla^mida?, the typical number of cervicals is twelve ; 

 following these are three cei-vico-thoracic vertebrae, i. e. those 

 bearing free ribs which do not articvilate with the sternum. The 

 hindmost pair bear uncinate processes but have no sternal 

 segment. In some, e. g. Syncdlaxis, there are only two paii's of 

 cervi co-thoracic vertebi'te, the hindmost pair just refei'red to in 

 such cases articulate with the sternum. But this point is of ^no 

 systematic value, though of interest morphologically. 



The thoracic vertebrae are six in number and have '^well 

 developed quadrangular neural spines, which may, as in Piprida? 



