Present distribulioii ol the so called Ratitae. 155 



A('l)i/(>niis itihh'hr(iii(lii Burckh E. Central Madag-ascar 



Recent. 

 Acjnioniis leni IIS M. E. & Grand Madagascar Recent. 



Acjii/oi'tiis inijllcri M. E. & Grand Central Madagascar 



Recent. 

 Acjii/oi'tiis iikxIchìus m. e. & Grand. . . . Central Madagascar 



Recent. 

 M iìlìevoniis hetsilei M. E. & Grand. . . . Central Madagascar 



Recent. 

 M iil I croni IR agil is M. E. & Grand S. W. Madagascar 



Recent. 

 'Miìììerornis ruais M. E. & Grand ,West Madagascar. 



T now give the definitions of the groups. For those of the 

 Struthiones, Rheae, and living Casuarii I am indebted to Mr. 

 W. P. Pycraft who kindly looked over the rough draft of this 

 lecture and gave me many valuable hints. He also drew up the 

 definitions of the A jderyges, Dinornithes and AepyornWhes, as 

 families. 



1. Struthiones. Vomer deficient posteriorly, not extending 

 backwards to reach the pterygoid, anteriorly extending forwards, 

 to conceal the parasphenoidal rostrum : the body of the vomer 

 embraced laterally by the maxillo-palatine processes: maxillo- 

 palatines hastate, the mesial borders gripping the vomer; anterior 

 palatine process of great size; pterygoid laminate; palatine rod- 

 shaped, fused proximally with external borders of pterygoid; 

 premaxilla wanting a palatine process: lachrymals continued back- 

 wards to fuse with a chain of supraorbitals and with the frontals, 

 enclosing a supra-orbital foramen: lachrvmal with an ossiculum 

 lachrymo-palatinum: nostrils holorhinal; anterior narial and 

 lachrymo-nasal fossa confluent. Axis vertebra with hypapo- 

 phvsis; cervicals greatly elongated: synsacrum with distinct 

 sacrais: total vertebrae 56: cervicals 17. Coracoid grooves of 

 sternum not widely separated. Metasternum with large posterior 

 lateral processes: procoracoid of great size: Corpus sterni with 

 conspicuous ventral prominence: no clavicles: Pelvis long and 

 narrow: post-acetabular ilia widely seperated from ischia, and from 

 one another in the mid-dorsal line: pubes fused caudad (a) with the 

 ischia and (b) with one another in the mid-ventral line: fore-arm 

 and hand much shorter than the humerus: toes two in number 

 (^id ^th^ Aftershaft wanting: large but degenerate remiges and 

 rectrices; Caeca enormous: Syrinx wanting. 



2. Rheae. Vomer deeply cleft anteriorly, exposing the para- 

 sphenoidal rostrum between a pair of long spurs: anterior pala- 

 tine foramen long, and slit-like: lachrymo-nasal fossa bounded 

 anteriorly by a bony spike: post-orbital process large. Orbital 



