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LIFE, IN ITS INTERMEDIATE FORMS. 
According to the same excellent authority, the Stag 
Beetle ( Lucanus cervus ) has been known to gnaw a hole 
an inch in diameter through the side of an iron canister 
in which it was confined, and on which the marks of its 
jaws were distinctly visible, as proved by Mr Stephens, 
who exhibited the canister at one of the meetings of the 
Entomological Society. 
Let us look at the powers of Insects exercised in the 
act of flying. The House-flies (Musca domestica), that 
wheel and play beneath the ceiling for hours together, 
ordinarily move at the rate of about five feet per second ; 
but if excited to speed, they can dart along through thirty- 
five feet in the same brief space of time Now in this 
period, as Kirby and Spence observe, “ a race-horse could 
clear only ninety feet, which is at the rate of more than 
a mile in a minute. Our little fly, in her swiftest flight, 
will in the same space of time, go more than one-third of 
a mile. Now compare the immense difference of the size 
of the two animals (ten millions of the fly would hardly 
counterpoise one racer), and how wonderful will the velo- 
city of this minute creature appear ! Did the fly equal 
the race-horse in size, and retain its present powers in the 
ratio of its magnitude, it would traverse the globe with 
the rapidity of lightning.”* Some of tho flies that haunt 
our gardens shoot along so rapidly that the eye cannot 
follow them in flight. 
Nor are these tiny creatures less masters of the arts of 
running and leaping. De Lisle mentions a fly so minute 
as almost to be invisible, which ran nearly six inches in a 
second, and in that spaco was calculated to have made 
* Introd. to Entomology. 
