EXTERNAL ANATOMY. WINO EEATHERS. 95 
treme shortness of their quills that they differ externally 
from the coots and other short-winged birds which 
fly. The wing of the penguin 47.), however. 
is of a totally different construction. In form it is 
more like the fin of a fish : the feathers assume the 
appearance of narrow scales, and they lie upon each other 
like the true scales of fishes (a), without any inequality 
of size, further than that those adjoining the bones (6) 
are smaller than such as are placed in the situation of 
the quills, (c) As instruments of flight they are of course 
entirely useless ; hut when the bird is once in the water 
(which it rarely leaves), their fin-like wings become a 
pair of powerful oars, urging on these birds at a prodi- 
gious rate. All the accoimts, in fact, given by navi- 
gators, favour the belief that the penguins, however 
helpless upon land, are yet the swiftest family of swim- 
mers in the feathered creation, just as the swallows, 
which represent them among the Tmesttorex, are the 
swiftest flyers. Thus does Nature, under structures the 
most opposite, preserve her uniformity of design, and 
tenaciously adhere to that law which gives a pre-emin- 
ent celerity of motion to the natatorial type. Thus, also, 
does it appear, that notwithstanding the vast difference 
in their conformation, the swallow and the penguin 
pursue their prey with a rapidity far .superior to that 
which can be accomplished by any other birds. 
(86.) There are a few deviations from the ordinary 
shape and regularity of the quills, which may be here 
noticed, but which do not affect the general form of the 
wing. One of these consists in the sudden contraction, or 
unusual development of some of the quills only ; the reason 
of which deviation is entirely unknown. In most of 
