282 
ON THE CLASSIFICATION OF BIRDS. 
not dark or sombre; and both will be more particularly 
noticed in a future volume. The reader should bear in 
mind, that our present object is directed to the cha- 
racteristics of groups, not of individuals : our task is 
not that of the biographer, or the collector of anecdotes, 
but rather that of the general historian of this part of 
creation. 
(234.) The genera composing this family may be 
here slightly mentioned, although our present state of 
knowledge will not allow so full an exposition of their 
affinities and relations as could be wished. The diffi- 
cidty of procuring such large birds for minute examin- 
ation, the rarity of most of them, and the few specimens 
that are in our museums, are all serious obstacles to 
attaining that acquaintance with the natural series of 
this family which can alone substantiate our present 
disposition of the genera. It has been stated, indeed, 
that, of the two typical groups, the first, or the restricted 
genus Vultur, has no caruncles or wattles either on the 
head or neck ,• while the possession of these appendages 
is stated to he the chief distinction of the vultures of 
the new world, forming the genus Cathartes. Our own 
observations, however, lead us to consider these as se- 
condary, and not primary, characters; in proof of which 
