No. 1.] NORTH AMERICAN PASSERES. III 
investigation. An affinity to the Indian and Australian Artamus 
(the species of which genus are often known as Wood-Swallows, 
or Swallow-Shrikes), has also been suggested ; and it may turn 
out that this genus, with its neighbors, may be the direct and 
less modified descendants of a generalized type, whence the 
Firundinide have diverged ; but at present it would seem as if 
the suggestion originated only in the similarity of certain habits, 
such as swift flight and the capacity of uninterruptedly taking 
and swallowing insect-food on the wing.” (A.N., Brit. Encyc., 
oth ed., Vol. XXIT., p. 730.) 
Huxley has said “the Cypselide are very closely related to 
the Swallows among the Coracomorphe” (P. Z. S., 1867, p. 
469); which is equivalent to my having substantially said, in 
another connection, that the Cypse/z are but profoundly modified 
Swallows, which latter are their nearest affines among the Pas- 
serves. So taking it all and all, I am at present inclined to be- 
lieve that the Swallows represent rather a low type of organiza- 
tion among the passerine birds. 
The Ampelide, which I have placed even lower in the scale 
than the Azrundinide, show in their organization all, or nearly 
all, those features which, as we now interpret them, are indica- 
tions of an inferior grade of avian organization. All of these 
characteristics I have elsewhere fully dwelt upon and pointed 
out in detail. 
In the body of the present memoir, the writer entered quite 
largely upon the question, as to the reasons for assigning the 
Lanide a \ow place in the passerine order, and it will be unnec- 
essary to take up that part of our subject here again. I am of 
the opinion that they are as low, if‘not the lowest type of bird- 
structure we have in our United States avifauna, among the 
Oscines. 
The classification of our sub-order of clamatorial birds, as rep- 
resented by the 7yrvannide, requires no especial comment from 
me, in this place; it has been left in the same position it occu- 
pies in the A. O. U. Check-List, and probably meets with the 
views of the majority of ornithotomists, as well as the systemat- 
ists the world over. It seems, I think, fully supported by all 
that we at present know of their economy. 
