THE IMPORTANCE OF BIRDS, ETC. 247 
All the birds remain as long as do the locusts; some 
even follow the mighty army in its migrations. 
Thousands of greedy birds must be satiated ! Hundreds 
of thousands of locusts are required to supply this 
demand; and should they number even billions, their 
ranks are yet in the end consumed! 
It is not necessary to go out of our native land in 
order to observe a similar instance; for in Germany, 
even, some species of insects appear in countless thou¬ 
sands. A wood infested by the caterpillar of the Pine 
Lappet, or the Gipsey Moth, is a terrible scene of 
devastation. Visiting the plagued spot, one crushes 
them under foot by dozens at every step. Their excreta 
fall from the trees like rain, and the odour of their 
decomposing bodies taints the very air for some distance 
around. The unfortunate forester clamours in vain; 
each day shows a loss of some thousands of thalers. He 
tries every means to arrest the enemy; but, alas, 
without avail! Man is powerless, without the assistance 
of birds, to extricate him from his difficulty, and cries to 
heaven for help ! His feathered friends, however, perform 
their part with untiring energy. Cuckoos, alone, can 
prey on hairy caterpillars with impunity; hut these birds 
are, unfortunately, nowhere very numerous. The eggs 
and pupse, however, of butterflies give ample occupation 
to thousands of active hunters. All the climbing birds, Tits, 
and Goldcrests, are unremittingly employed in seeking 
out and devouring them. It is a recognized fact that the 
winter following a plague of caterpillars, such as I have 
described, finds the forest inundated with countless 
numbers of Titmice and Goldcrests, as well as Wood¬ 
peckers of every kind. The forester who is well 
acquainted with his business knows their worth, and 
