240 
Destructive Insects and Utility of Birds. 
vorous birds near at hand. Sensible gardeners every year more 
and more discourage the slaughter of sparrows. 
All the species of warblers (Sj/lvia orphaa), the red wren (^Arun- 
dinacea), the yellow wren [Sylvia trochilus), the white wagtail 
{3Iotacilla alba), the stonechat [Saxicola rubicola), as well as the 
different sort of shrikes ( Vaniits), are excellent insect-hunters, and 
particularly the spotted fly-catcher (Muscicapia r/risola), which bird 
it is better to keep at a distance from bee-hives, whose vicinity it 
frequents. In vineyards the blackbird does not compensate by 
its services for the damage it causes to the crop ; but in other 
places they ought to be protected, for they devour numbers of the 
destructive earth-caterpillar — a task also performed by the agile 
common stare [Sturmis vulgaris), which likewise delivers cattle 
at pasture from worms, flies, gadflies, &c. 
Swallows are most active insectivora — we should therefore 
protest against the custom of capturing them for food, which 
prevails in some parts of Germany; we should intercede also 
for the lark, who, though of use to the agriculturist, finds here 
an implacable enemy in man. We will now just take notice of 
a few of the larger class of birds, which are of very important use 
to our different sorts of culture. The cuckoo is the first on the 
list. Nature has formed this very remarkable bird for the express 
destruction of hairy caterpillars, which other birds cannot eat, 
and has organised its stomach for the easy digestion of such 
food. In 1847 an immense forest in Pomerania was on the 
brink of utter ruin, caused by the havoc of caterpillars. It was 
suddenly and very unexpectedly saved by a band of cuckoos, 
who, though on the point of migrating, established themselves in 
the place for a a few weeks, and so thoroughly cleansed each 
tree that the following year neither depredators nor depreda- 
tions were to be seen. The cuckoo, like the smaller insect- 
eaters, eats all the dav long, for the caterpillar is full of watery 
matter and contains but little solid nutriment. By careful 
observation it was ascertained that the cuckoo devours one 
caterpillar every five minutes, or 170 in a long day. The hairy 
stuff sticks to the mucous membrane of the bird's stomach, so as 
often totally to cover it. If we assume that one-half of the 
destroyed insects are females, and that each contains about 500 
eggs, one single cuckoo daily prevents the reproduction of 42,500 
destructive caterpillars. How many men could do the like in 
one day ? 
The race of woodpeckers almost rival the cuckoo in utility, 
and, though unappreciated, are the good genius of our woods. 
They are full of vigour and courage. When we pass under a tree, 
how eagerly they look down upon us, seriously and attentively, 
with their clear brilliant eye ! almost saying, " Friend, dost thou 
