EXTERNAL ANATOMV. SWIMMING FEET. l6l 
families, in being placed almost as forward as in the swifts. 
We know too little of the manners of these birds in their 
watery element, to conjecture the sort of influence this 
structure would exercise during the act of swimming. It 
seems, however, from the united testimony of voyagers, 
that when upon land the penguin's attitude is perfectly 
erect : indeed, it could not be otherwise, the legs being 
placed so far back, and past the equilibrium of the body. 
The same position is assumed by the cormorants when 
watching for their prey ; and yet the form of the hind 
toe in these two genera is so different, that this general 
character in their habits will not explain 
the reason of the variation. In the penguin 
(fig.SS.) the tarsus is so short as almost 
to be confounded with' the sole of the 
foot ; and it is probably rested upon the 
ground for its whole length when the 
bird walks, just as in the bear and other 
plantigrade quadrupeds ; it is also re- 
markably broad : the hind toe is placed in 
front, and on the inner margin ; but it is 
so unusually small, that, but for its short, 
but well defined claw, it would not be 
perceived. This claw is without any vestige of a web, 
or of a lobe, and is quite disconnected with the others : 
of the three anterior toes, the middle is the longest, 
the outer rather less, and the inner by far the 
shortest. The whole foot is remarkably flattened, being 
near twice as broad as it is thick, as if to enable the 
bird to cover a greater breadth of ground than ordinary. 
The cormorant’s foot agrees in having the hinder toe 
brought forward ; but here its similarity to that of the 
penguin ceases. The tarsus is somewhat longer, and 
instead of being compressed in front, is compre.ssed on 
the sides ; the toes are long, and so arranged in their 
relative lengths, that the outermost is the longest, and 
the three others rapidly diminish in length ; all four 
being connected to each other by a membrane which 
reaches to the claws. From this it would appear that such 
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