302 FOOT-NOTES FROM A PAGE OF SAND. 
for the perfect opposition of the hind and front toes, as the 
thumb of our hand opposes the fingers; it infallibly suggests 
the idea of something to be clasped between—of grasping 
some object; the suggestion amounts to a moral certainty 
when we dissect and find among typical perchers.a special 
muscle for the freer and more advantageous working of this 
hind toe in opposition to the others. Such birds then, live 
where their foothold is not upon a flat surface, as the ground, 
but upon slender, cylindrical, claspable supports, as are 
found in trees and bushes. But there cannot be much plain 
walking done among twigs; the birds must constantly 
spring from one to another branch, and when they happen 
to descend to the ground it is not likely they would at once 
change a habit inborn and inbred for ages. So with certain 
exceptions, not necessary to point out here, Jnsessores are 
hoppers, as distinctively as all birds below them are either 
alkers or Swimmers. 
This bird's wings never touched the sand, yet the marks 
show the shape of the wing as plainly as the character of the 
feet. The wings were flat, long, narrow and pointed, cut- 
ting the air like blades. We learn this from the few indis- 
tinct seratches on the sand just before the prints became 
perfect. The bird came gliding swiftly and low, an 
scraped the sand before its wings were closed; to do this re- 
quires a wing large or at least long. For all heavy bodied 
birds, or birds with wings small for their weight; or with 
short, rounded and concave wings—all these, however fast 
they may whirr along when fairly on wing, must drop 
quietly, if flying slowly, or arrest their motion abruptly 
and forcibly, if flying rapidly, to avoid shock on alighting; 
in either case they drop plump, and find their feet at once. 
Now of all our true walking or wading birds the Galline 
(Grouse, Quail, ete.) and the Paludicole (Rails and Galli- 
nules) conform to these last mentioned particulars; so does 
the Heron family, and these, moreover, have a long hind toe. 
It could have been neither of these. The circle of possibili- 
