346 ON THE CLASSIFICATION OF BIRDS. 
Casuarius, Ray. Cassowary. Bill strong, emarginate. 
Head and neck naked ; the former with an elevated — 
protuberance, the latter with wattles. Feet three- 
toed, all placed forwards. 
C. galeatus. Pl. Enl. 313. 
Dromiceus, Vieil. Emu. Head smooth, feathered. 
Bill short, depressed, resembling that of Platyryn- 
chus. Under mandible serrated. Nostrils naked, 
linear, placed in the middle of the bill. Throat 
naked. Feet with three toes, placed forward. Tar- 
sus strongly serrated behind. The rasorial type. 
Frugivorous and herbivorous. . 
D. Australis. White’s Voy. pl. 1. , 
Apternyx, Shaw. Kiwi. Bill slender and considerably 
lengthened. Feet short, with three toes before, and 
a spur, representing the hallux, behind. The tenuiros- 
tral type.* 
A. Australis. Zool. Trans. i. pl. 10. 
Rhea, Brisson. Bill straight, depressed ; the tip bent 
down and hooked. Head feathered. Feet with three 
toes before, and a callous protuberance behind. Wings 
developed, but too short for flight. Insectivorous. 
The fissirostral type. 
R. Americana. Auct. 
Famiry COLUMBIDE. Pigeons. t 
Feet very short. Wings long. 
'* There is scarcely any bird out of the grallatorial order, which so beau- 
tifully represents it as this. Mr. Yarrell is even struck by the resemblance 
of the bill to “ that of an ibis.”” Although, perhaps, the resemblance of 
this part, from its thickened termination, is much more similar to Scolopaz. 
f So far as I have yet proceeded in the analysis of this group, I have formed 
the following opinions :—1. That the true pigeons constitute only one of 
the five primary divisions ; just as the true woodpeckers (Pcian@) form only 
one group in the circle of Piciade, so that both are of equal rank and 
value. 2. 'It consequently follows that the four other divisions of the Co-— 
lumbide@ are either represented by birds which have not been yet disco- 
vered, or by types very peculiar intheir general appearance. 3. Of this ~ 
latter I consider that Opisthocomus connects the Columbide with the Me- 
galopide, by means of Dicrolophus, and that Chionis is the grallatorial 
representative. Of the two remaining types, one of which is the fissirostral, 
I am quite ignorant: I think it more than probable, however, that the 
true pigeons form one circle, and not two. 
