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place, as wanted, along the mud and weeds amid which it conceals 
itself, without rising from the bottom. 
This fish belongs to a family in which there are many other 
allied forms that must have been originally derived from the 
angler, but which show an alteration in structure and habits due 
to altered surroundings. Fish that rarely leave the sea-bottom 
seem to have a tendency, in the lapse of many generations, to get 
to lower levels; and thus the anglers “have gradually found 
their way to the greatest depths of the ocean; retaining all 
the characteristics of their surface ancestors, but assuming the 
modifications by which they are enabled to live in abyssal depths.” 
The angler’s rod is there of no use, and other means of getting 
its food, and probably a different kind of food, are required. 
As these last fishes are always getting into deeper and deeper 
waters, so—to reverse the picture—there are others that seem’ 
impatient of their proper element, and as if trying to escape from 
it altogether. I allude to the flying fishes, so common in tropical 
seas, which in certain states of weather suddenly dart out of the 
water—not a mere spring for a moment into the air to fall down 
again directly, as many fishes may be seen to do occasionally—but 
to pursue an aerial voyage of one or two hundred yards, rising 
also in some instances to the height of 40 feet. How are they 
enabled to undertake this long flight? By the help of enormously 
developed pectoral fins, very broad and equalling the entire 
length of the body, which must have been gradually evolved in 
the course of ages by use and natural selection—so at least, I 
suppose, Darwin would say. 
And there are stranger things than these. Who would ever 
have thought of fish climbing trees? Yet there is a species of perch 
found in India, which, leaving its native element, is venturesome 
enough to attempt this feat. It is the Perca scandens of Linnzus, 
and is called by the natives in the Malay language the “Tree- 
climber.” There is a paper in one of the earlier volumes of the 
