PLATE 24. 



{Natural sisie.) 



Fig. 1. Snpramaxillary, nasals and lachrymal of Phalcobseuus (Seues) australis. 



2. Coracoid apparatus of Ibycter americauus. 



3. Coracoid apparatus of [Rostrhamus sociabilis (the Buteonine form most like 



Ibycter in external form). 



4. Sternum of Milvago (cliimacMma ?). 



5. Sternum of Ibycter americanus. 



6. Stermim of Polyborus tharus. 



