al 
8 BIRD GALLERY. 
the palatine, but forming a close union either by fusion or by over- 
lapping suture with the base of the vomer. 
The majority of the members of this group have become flightless, 
a fact which has brought about many modifications of the skeleton 
and feathers. The Tinamous alone have retained the power of 
flight. 
The Ratite are divisible into seven Orders, probably derived from 
three distinct stocks. Each Order can be readily defined, and presents 
one or more points which indicate extreme specialisation. 
On account of the structure of the palate, the members of this section 
may be regarded as the most primitive of living birds. 
The seven Orders of the Ratite are the following :— 
1. Struthioniformes . One genus, Struthio. 
2. Rheiformes..... One genus, Rhea. 
3. Dinornithiformes . ) 
4, Apyornithiformes J 
5. Casuariiformes... Two genera, Casuarius and Dromeus. 
6. Apterygiformes.. One living genus, Apfteryx, and two 
extinct genera. 
7. Tinamiformes.... Numerous genera. 
Numerous genera. Extinet forms. 
The characters by which the Orders are distinguished are fully 
explained in the table-case in the first bay. 
Case 1 and 
Central Case Order I. STRUTHIONIFORMES. Osvricu-rriBe. 
Bay. | , 
= Though closely allied to the Rheas, which they resemble in general 
appearance, the members of this order may be at once distinguished 
from all others by possessing only fro toes. Of these the one corre- 
sponding to the middle of the three anterior toes in ordinary birds (the 
third of the complete set) is much the largest and supports the greater 
part of the weight. It bears a stout pointed nail. The smaller outer 
(or fourth) toe often wants the nail. The whole of the head and neck 
as well as the legs are bare, or only covered with short down. The body- 
feathers are single, having no aftershaft, and the feathers of the wings 
and tail (corresponding to the ‘remiges’ and ‘rectrices’ of ordinary 
birds) are of considerable size, but soft and plumose. 
Family Srrurntonip&®. Os?ricHes. 
The Ostriches, the largest of living birds, are represented by the 
single genus Struthio, which contains at least four living species 
