CLASSIFICATION OF VERTEBRATA 



31 



1 . Sirnthiones, Wagler. Two toes (3rd and 4th). With 

 symphysis pubis; unique in birds. 



Struthio. Africa and Arabia; Miocene of Samos; 

 Pliocene, Sivalik Hills. 



2. Rheae. Three toes. With long ischiadic symphysis ! 

 Rhea. Neotropical. 



Mesembriornis. Miocene or Pliocene, Argentina. 



3. Casuarii, Kaup. Three toes. Aftershaft as long as 

 the other half. 



Casuari us, Dromaeus. Australian region. 

 Hypselornis. Pliocene, Sivalik Hills. 



4. Apteryges. Four toes. Long, slender bill. 

 Apteryx. New Zealand. 



5. Dinomithes. Three or four toes. Bill short. Anterior 

 extremities extremely reduced. 



Dinornis. Numerous species, recently extinct. New 

 Zealand. 



6. Acpyornithes. Four toes. 



Aepyornis. Recently extinct. Madagascar. 



2. Division— NEORNITHES ODONTOLCAE, Marsh. 

 Murine, flightless, without sternal keel.' Teeth in furrows. 

 Cretaceous. 



Enaliornis. England ; vertebrae chiefly biconcave. 

 Hesperornis . U.S.A. ; vertebrae heterocoelous. 



3. Division — NEORNITHES CARINATAE, Merrem. 

 With keeled sternum. 



1. Order Ichthyornithes. Vertebrae amphicoelous. Teeth 

 alveolar. With small pygostyle. With incisura ischiadica. < 



Cretaceous of Kansas. 

 Tch thyorni s. Apatornis. 



2. Order Colymbiformes. Plantigrade, nidifugous, aquatic. 

 Fourth toe largest, hallux short ; all toes webbed. Metatarsus 

 laterally compressed with high, pyramidal epicnemial crest. 

 Bill straight, pointed, with simple sheath. 



1. Sub-order COLYMBI. Front toes completely webbed. 

 Patella much reduced. 



Colymbus. Periarctic. 



2. Sub- order PODICIPEDES. Toes lobated. Patella 

 absent. 



