C. CLASSIFICATION ACCORDING 
TO COLOUR 
I. Black. 
II. Blue. 
III. Brown. 
IV. Coffee or fawn colour. 
V. Green. 
VI. Grey. 
VII. Pink. 
VIII. Red. 
IX. White. 
X. Yellow. 
Colour affords the easiest means of identify- 
ing the great majority of birds, but in many 
cases the colours displayed, although con- 
spicuous and easily recognised, are not of a 
nature to admit of strict classification. ‘Take, 
for example, the blues—various species display 
almost every known shade from slaty grey to 
turquoise, from purple to ultramarine and 
indigo. To attempt to distinguish in the 
lists between the many shades of blue would 
3! 
