564 STRUCTURAL CHARACTERS 



(d) VERTEBRAL COLUMN. 



Heterocalous vertebra with saddle-shaped surfaces for articulation one with another. 

 Opisthocoelous vertebrce wherein the hinder articular surface is cup-shaped, and the 

 anterior spherical. 



(e) VISCERA. 



Ambiens a superficial muscle extending from the pectineal process of the pelvis, along 

 the inside of the thigh, and across the knee to the calf of the leg. 



Cceca the blind diverticula of the intestine, marking the junction between the large and 

 small intestine. 



Syrinx the voice organ which in birds is formed at the bottom of the windpipe. 



Tracheo-bronckml syrinx a syrinx formed in part by the windpipe proper, and in part 

 by the right and left branches, or bronchi, communicating with the lungs. 



KEY TO CLASSIFICATION 



ORDER: PASSERIFORMES 



All the toes free, hind-toe well developed; aftershaft vestigial; wingeutaxic; oil-gland 

 nude ; palate segithognathous ; hinder border of sternum with a single pair of notches ; deep 

 plantar tendons free; ambiens absent; caeca vestigial; not less than five pairs of voice muscles; 

 young nidicolous. 



1. FAMILY CORVID.ffi CROWS. 



Eleven remiges, the outermost shortest, but longer than the major coverts of the hand ; nostrils 

 without operculum, bristle covered ; tarso-metatarsus scutellate in front. Sexes alike ; 

 young like the adult. 



(a) Genus Corvus. Wings long; primaries ernarginate, outermost relatively long; 



tail shorter than the wing ; beak as long as the head ; colour black, or black and 

 grey. (Vol. i. p. 1.) 



(b) Genus Pica. Tail long, fan-shaped ; wings short and rounded ; outermost 



primary very short, much attenuated and sabre-shaped. (Vol. i. p. 8.) 



(c) Genus Garrulus. Wings short and rounded; bristles covering nostrils very 



short ; major coverts of the hand bright blue, barred with black ; crown feathers 

 long and erectile. (Vol. i. p. 8.) 



(d) Genus Nucifraga. Wings short and rounded ; bristles covering nostrils short ; 

 beak long, cylindrical, slightly swollen at the base, and blunt-pointed. (Rare 

 Birds, vol. iv. p. 463.) 



(e) Genus Pyrrhocorax. Wings long ; bill long, slender, decurved ; nostrils opening 



nearer to the toinium than the culmen, concealed by short bristles ; claws long 

 and much curved; beak and legs red. (PI. 7, vol. i. p. 60.) 



2. FAMILY FRINGILLID.E FINCHES. 



Ten primaries, the outermost vestigial ; beak conical, pointed ; nostrils concealed by short 

 recurved feathers. 



(a) Genus Ligurinus. Beak sub-cylindrical; three outermost primaries equal. (Vol. i. 

 p. 64.) 



