38 NEBRASKA ORNITHOLOGISTS' UNION 



fossil remains. About all the palaeontologist can do in such cases is 

 to arrang-e birds by families. However, the occurrence of fossil forms 

 of certain groups, such as larks, crows, finches, etc., is well determined. 

 Contemplation of the embryonic condition of birds gives retrospective 

 glimpses and hints at the ancestry of groups of birds, but it is by 

 palaeontological methods that those fundamental structural characters 

 are revealed which lead to the establishment of laws and exact rela- 

 tionships, and it is along this line that the ancestry of birds must be 

 sought. 



CLASSIFICATION 



No ornithologist can fail to be interested, as well as instructed, by 

 a perusal of the various arrangements of birds proposed by different 

 authors, from Linnaeus to Stejneger, Fxirbringer, and Gadow, which 

 may be found in Bronn's Klassen und Ordnungen des Thier-reichs 

 (Band. VI., Abth. 4., Voegel. Leipsig: 1893. Pp. 1 to 303). It is well 

 understood that no classification yet proposed is satisfactory — all are 

 necessary and helpful rather than exact. 



Palaeontologists are disposed to emphasize the toothed and the tooth- 

 less condition, as will be seen by the following classification; while this 

 may not be a true basis of classification it is at least very suggestive, 

 and for that reason is here adopted. 



CLASS AVES (BIEDS) 



Sub-class Archaeornithes (Ancient Birds) 



DivisioH 1 — Saunirae ( Lizard-tailed ) 

 Toothed 

 Order 1— Archaeopteryges : Archaeoptery.v (p. 15). 



Sub-class Neornithes (Recent Birds) 



Division 2 — Ratitae (without a keel) 

 Toothed series 

 Orders — Odoutolcae : Hesperornis (p. 21). 



Toothless series 

 Orders — Aepyornithes : Aepyornis (p. 27). 

 Order 4 — Apteryges: Aptery.v, Kiwi (p. 28). 

 Order 5 — Dinornithes : Moas (p. 28). 



Order 6— Megistanes : Casuarius, Cassowary; Dromaem, Emeu (p. 29). 

 Order 7 — Rheornithes : Rhea, American Ostrich. 

 Orders — Struthioruithes : Struthio, Ostrich. 



Order 9— Stereornithes : Phororhacos (p. 30), Brontoniis, Stereornis. 

 Diatryma, Dasornis. 

 Gastornis (p. 31). 



(Of very doubtful position. Probably degenerate carinates, 

 belonging near Gruiformes. ) 

 [Division Odontolcae placed here by most taxouomists.] 



Division 8 — Carinafne (with a keel) 

 Toothed series 

 Order 10 — Odontormae : Ichthyornis (p. 31). 

 Apatoruis. 



