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ON THE DOWN-PLUMAGE AND MOUTH- 

 COLORATION OF NESTLING BIRDS. 



I. 



BY 

 C. B. TICEHURST. M.A., M.R.C.S., M.B.O.U. 



STONECHAT Pratincola rubicola (L.). 

 Down. Colour. — Dark grey. 



Character. — Modei-ate length. Scanty on the spinal and 



humeral tracts. 



Distribution. — Inner supra-orbital, occipital, humeral and 



spinal. 

 Coloration of the Mouth. Inside, yellowish ; no spots ; 



externally, flanges very pale yellow. 



REDSTART Ruticilla phcenicurus (L.). 

 Down. Colour. — Dark grey. 



Character. — Well marked and long, except in dorsal and 



humeral tracts, where it is short and scanty. 



Distribution. — Outer supra-orbital, inner supra-orbital, 



occipital, humeral and spinal. 

 Coloration of Mouth. Inside, lemon-yellow ; no tongue 



spots ; externally, flanges very pale yellowish white. 



WILLOW- WARBLER Phylloscopus trochilus (L.). 

 Down. Colour. — Very light grey. 



Character.— Fairly long and scanty. 



Distribution. — Inner supra-orbital, occipital, humeral. 

 Coloration of Mouth. Inside, orange ; no tongue spots ; 



externally, flanges very pale yellow. 



WOOD- WARBLER Phylloscopus sibilatrix (Bechst.). 



Down. Colour. — Light grey. 



Character. —Fairly long and scanty. 



Distribution. — Inner supra-orbital, occipital, humeral. 

 Coloration of Mouth. Inside, yellow ; no tongue spots ; 



externally, flanges yellowish. 



REED-WARBLER Acrocephalus streperus (Vieill.). 



Down. Absent. Skin of body very dark. 



Coloration of Mouth. Inside, orange; two long oval, 

 symmetrical, black tongue spots at base of tongue ; exter- 

 nally, flanges lemon-yellow. 



