,36 
Transactions Texas Academy of Science. — 1906. 
Cones, E. 
1903. Key to North American Birds. Fifth edition. Boston. 
D ’Alton, Ed. 
1837. De Strigum Musculis Commentatio. Halae. 
Forbes, W. A. 
1877. On the Bursa Fabricii in Birds. Proc. Zool. Soc., London. 
Fuerbringer, M. 
1888. Untersnchnngen Zur Morphologie und Systematik der 
Yoegel. Amsterdam. 
Gadow, H. 
1891. Yoegel, Bronn’s Klassen und Ordnungen des Thierreichs. 
Leipzig. 
Garrod, A. H. 
1873. On Certain Muscles in the Thigh of Birds, and on their 
Yalue in Classification. Ibid. 
Nitzsch, C. L. 
1867. Pterylography, translated (by W. S. Dallas) from the 
German. Ray. Soc., London. 
Shufeldt, R. W. 
1886. Contribution to the Anatomy of Geococcyx Califorianus. 
Wunderlich, L. 
1884. Beitraege zur vergleichenden Anatomie und Entwicklungs- 
geschichte des unteren Kehlkopfes der Yoegel. Nov. 
Act. Leop. Akad. 
Description of the Plates. 
The following abbreviations have been employed: 
Ab., Musculus pectoralis, pars abdominalis. 
A. C., Anterior commissure. 
Ad., Adrenal. 
Ap. tb. m., Apex tuberculi medialis humeri. 
Bf., Bursa Fabricii. 
Bi., Musculus biceps brachii. 
C., Coracoid. 
Cae., Caeca. 
Cb., Cerebellum. 
Cer., Cerebrum. 
Cj., Conjunction of Duodenum and Gizzard. * 
Cl., Clavicle. 
Clo., Cloaca. 
Con., Processus supracondyloideus lateralis of the humerus. 
Cor. br. a., Musculus Coraco-brachialis anterior. 
Cor. br. ai., M. coraco-brachialis anterior insertion. 
