Our Common Birds and How to Know Them 
A scale of sixteen steps is recommended in the Cope of the American Ornithologist’s 
Union as being ‘‘ adequate to all practical requirements of even a refined system of classi- 
fication.” 
It is as follows : 
t Kingdom. 5 Super-order. 9 Family. 13 Species. 
2 Sub-kingdom. 6 Order. to Sub-family. 14 Sub-species. 
3 Class. 7 Sub-order. 11 Genus. 15 Variety. 
4 Sub-class. 8 Super-family. 12 Sub-genus. 10 Individual. 
It would indeed seem to a layman that these sixteen grades afforded sufficient scope 
for the classification of any ordinary bird. 
All birds, whether living or extinct, belong to the Class Aves. In this Class there are 
five sub-classes, viz. : 
SAURUR#. Ratit&. 
ODoNTOTORM®. CARINAT. 
OponTOLce. 
