PICO-PA!SSERES. 



Fijr. (! 



st-i 



in.ti 



Syrinx of Rook (T.fruyilet/tis), to show the aiTangement and Acroniyodian 

 attachments of the intriusic muscles. — Fig. o. Lateral view of syrinx. 

 Fig. G. Dorsal surface of syrinx, st, muscle running from trachea to 

 costal process of sternum ; II, III, second and third bronchial semi- 

 rings, tlie first concealed by muscles ; 1, 2, 3, 4, 5, G, syringeal muscles ; 

 m.t.i, the membrana tympaniforrais interna. 



Subdivision A. PASSEHES NOllMALES. 

 Family CORVID^. *. 



A. Outer and inner toes subeqiial in length. Fig. 4 (vide p. 5). 



B. No bony nasal septum, but a corresponding deficiency in the 



palate. 



C. Palatines obtusely quadrate near their posterior extremity. 



(Fig. 2.) 



Fig. 7. 



Lateral view of cranium of Rook ( T. /ni(/i7ff/tis). (From a specimen in 

 the Museum of the Royal College of Surgeons.) io.f., interorbital 

 fenestra ; f.~P; frontal zygomatic process ; s.z.p., squamosal zygomatic 

 process. 



* Cf. W. K. Parker, " On the Structure and Development of the Crow's 

 Skull," M. Micr. .lourn. viii. pp. 217--22G, pis 34-.3G (1872); also Dr. 

 Shiifeldt's ' Myology of tlie Raven,' 8vo. 18W. 



