386 



jNIr. C. W. Andrews on the Skull, 



the present specimen. In this latter ossification probably 

 took place from a pair of centres^ the pleurostea (mesosterna), 

 which gradually extended towards the middle line^ where 

 tr9,ces of their union are still visible {s, PI. IX. fig. 1). The 

 antero-lateral process, however, may, as in Rhea, have 

 ossified from a second pair of centres (proostea). 



From the foregoing description it will be gathered that in 

 ^pijornis the sternum has undergone greater reduction than 

 in perhaps any other bird, and that to some extent, in its 

 similarity to the sternum of the New Zealand Ratitse, it 

 supports the conclusions derived from the cranium. 



Fig. A, left coraco-scapula oi^pyornis; Figs. B & 0, supposed liiimeri. 

 {\ natural size.) 



sc, scapula ; c, coracoid ; pc, precoracoid process ; f.spc, supra-coracoid 

 foramen; f/!., glenoid cavity; h., head; t.?7i., tnhercuhnn mediale 

 (inner irofliank-r) ; crJ., crista lateralis (pectoral crest). 



