FLIGHTLESS BIRDS. AN 
the mountain sides caused by the birds in their nocturnal 
rambles, marching in line one after the other. Its plum- 
age of mixed green and brown wonderfully assimilates to 
the vegetation amongst which it lives, so that at a little 
distance it is almost impossible to distinguish it. It is 
said to be a clever, intelligent bird, of a playful disposi- 
tion, and, in captivity, to contract a strong affection to 
those who are kind to it. It has ample wings, but all 
observers testify to its complete inability to fly, at most 
merely using its wings to break its fall when dropping 
from a height to the ground, and not always even on those 
occasions. ‘This inability to fly is correlated in a very 
interesting way with the practical loss of the carina 
sterni. The sternum, as is well seen in the skeleton before 
you, is almost flat, and probably in this respect approaches 
the Ratitee more nearly than any other Carinate bird; the 
keel is indeed there, but it 1s reduced to a very low median 
ridge and is clearly almost obsolete. Such a case as this 
shows us that too much importance may easily be attached 
to the absence of a keel to the sternum in the Ratite birds 
in discussing their phylogeny. If in Stringops, an un- 
doubted member of a tribe of strong flying Carinate birds, 
the keel of the sternum can be reduced by disuse of the 
wings to the low ridge seen in the specimen, it is not in 
the least to be wondered at that in the Ratite birds, a 
much more ancient type than that of the Psittaci, it should 
have disappeared altogether from the same cause; and 
hence, as before argued, the absence of a keel in the Ratite 
birds by no means negatives their descent from a Carinate 
stock. The causes which have led to the loss of the faculty 
of flight in Stringops are not difficult to trace, and run on 
parallel lines to the similar instance of the Dodo, but we 
have, in the case of Stringops, the great advantage of a 
definite knowledge of the habits of the bird. 
