AS MEANS OF IDENTIFICATION 569 



(a) Genus Chelidon. Tail deeply forked, the outer pair of feathers produced into long 



streamers. (Vol. ii. p. 277.) 



(b) Oenus Hirundo. Tarso-metatarsus feathered to the toes; tail forked. (Vol. ii. 



p. 282.) 



(c) Genus Riparia. Tarso-metatarsus with a tuft of feathers just above the hallux 



(Vol. ii. p. 284.) 



II 



ORDER: CORACIIFORMES 



Young nidicolous, nestling down often vestigial or wanting ; holorhinal, nares impervious ; 

 ambiens wanting ; the feet if zygodactyle never associated with a desmognathous palate. 



SUBORDER : PICI WOODPECKERS 



Young nidicolous, nestling down vestigial or wanting; feather-tracts very narrow; wing 

 eutaxic ; basipterygoid processes wanting ; spina interna wanting, spina externa large ; hinder 

 border of sternum double notched ; feet zygodactylous. 



1. FAMILY PICID.E. 



Tongue protrusible; oil-gland tufted; basipterygoid processes of skull wanting; palate 

 saurognathous ; spina interna wanting. 



(a) Genus Pious. Beak long, dense, blunt-pointed, laterally compressed and broad 

 at the base ; nortrils oval, covered with bristles ; tail feathers pointed and spine- 

 like, outer pair\stigial ; 3rd and 4th toes equal ; prevailing colour yellowish 

 green and red. (Vol. ii. p. 318.) 



(b) Genus Dendrocopus. Distinguished from Gecinus in having the 4th toe much 



longer than the 3rd ; prevailing colour black, white, and red. (Vol. ii. p. 320.) 



(c) Genus lynx. Beak short, sharp-pointed ; nostrils linear, partly closed by 



membrane ; outermost (10th) primary minute ; tail feathers normal (not spiny), 

 outer pair vestigial ; proximal end of planta with a heel-pad ; prevailing colour 

 brown and grey. (Vol. ii. p. 342.) 



SUBORDER : CYPSELI SWIFTS 



Oil-gland nude ; wing eutaxic ; hinder border of sternum entire ; humerus excessively 

 shortened ; manus very long ; ten primaries, of which the outermost is the longest ; secondaries 

 not exceeding six to seven. 



2. FAMILY CYPSELID.S. 



Beak excessively short, hooked, wide at the gape, which extends below the eye; foot 

 pamprodactylous. 



(a) Genus Cypselus. Tail of ten feathers, deeply forked ; tarsus feathered. (Vol. ii. 

 p. 350.) 



(b) Genus Acanthyllis. Tail short and even, the shafts prolonged beyond the vane 



to form spines ; tarsus scutellated. (Vol. iv. p. 501.) 



SUBORDER: CAPRIMULGI NIGHTJARS 



Dorsal feather-tract forked ; wing diastataxic ; tarso-metatarsus very short ; toes free, 

 middle toe with pectinated claw ; spina externa vestigial, spina interna wanting ; cseca large ; 

 young down-clad. 



