FOOT-NOTES FROM A PAGE OF SAND. 301 
Each foot-print was of three marks only; clearly then 
made by a three-toed bird ; or, if by one with four toes, the 
fourth was too shor£ to reach and impress the ground visibly, 
or else was joined to the leg too high up. The three marks 
all point forward ; then the hind toe, or hallux, as it is called, 
was the missing or rudimentary one. Now, unless the bird 
was of a kind unknown to naturalists, which is highly im- 
probable, it must have belonged to one or the other of two 
groups—the Walkers and Waders, or the Swimmers— 
named, respectively, Cursores and JVatatores, since no bird of 
the only other remaining group (Jnsessores) has none, or a - 
rudimentary hind toe.* Birds, however, cannot swim unless 
their feet are fashioned into paddles of some sort. We only 
know of this being done in two ways: either by stretching 
a membrane between the toes, making a webbed foot, or by 
fringing of the toes by broad membranes, making a lobed 
foot. But either of these feet, pressing the glassy sand, 
would have shown its pattern. Clearly then the bird was 
neither palmiped or lobiped— it was not one of the Wata- 
tores; it must have been a Wader. Other reasoning, from a 
different premise, brings us to the same conclusion. The 
marks were not in pairs, but alternating, each with its fellow 
of the other line; the bird did not hop or leap, but walked 
or ran bringing one leg after the other, whence we legitimately 
infer that it was not one of Jnsessores or Perchers ; for these 
hop. But it might be asked, how do we know that the 
perchers hop instead of walking when on the ground, since 
we are agreed that we never yet saw a live one to find out 
by observation? Yet it is easy to reason up to such a point, 
that assumption is virtual certainty. For the hind toe (or 
each hind toe when there are two) of the Jnsessores is long, 
is inserted on a level with the anterior ones, and is armed 
with a curved claw as the others are. This arrangement is 
*' To this and all other unqualified general statements in ornithology there are 
technical obiecti 1 1 t ti not. however. i lidati 1 
rules. 
