x INTRODUCTION. 
born able to run and feed themselves in a few hours, than they are to the desmo- 
gnathous Pelecano-Herodiones, which differ from them in having the young born 
helpless and requiring to be fed by their parents for many days? 
Probably most ornithologists will, & priori, regard the condition of the young at 
birth as a less reliable character than the arrangement of the palatine bones and the 
feather-tracts: but if the relative importance of these characters is to be decided 
upon by the results of their use in the diagnoses of the subclasses into which birds 
may be divided, I for one am disposed to vote for the chicks and adopt the 
alternative scheme, which is elaborated on the next page. 

