340 



THE NATURALIST. 



lished themselves in the vicinity for a few weeks, and so thoroughly depo- 

 pulated each tree that the ensuing year neitlier depredators nor depredations 

 were to be seen. The cuckoo, like the smaller insectivora, eats all the day 

 long, for the caterpillar is full of aqueous matter and contains hut little solid 

 nutriment. By careful observation it has been ascertained that the cuckoo 

 devours on an average one caterpillar every five minutes, or 170 in a long day. 

 The capillaceous stuff adheres to the mucous membrane of the bird's stomach, 

 so as very often totally to cover it with a capillose lining. If we assume that 

 one-half of the destroyed insects are females, and that each contains about 

 500 ova, one single cuckoo daily prevents the reproduction of 42,500 des- 

 tructive caterpillars. The woodpecker almost rivals the cuckoo in utility, 

 and, though unappreciated, is the good genius of the woods. Their chief 

 victims are some very mischievous insects, such as the Nodua, the Lasio- 

 campa, the Sphinx lyinastri, the Tisodes pini, the Trachea piniperda, Sfc. 

 Amongst birds of prey, Raptores, many insectivora are to be found, and such 

 often are well worthy of protection. All the smaller birds of prey^ as also 

 some larger ones, feed their young on insects, and they themselves, when 

 incubating, scarcely touch anything else. The most useful members of the 

 order incontestably are owls, which being extraordinarily gifted for the work, 

 devour in their twilight haunts immense quantities of insects, principally 

 nocturnal lepidoptera and their larvse. Some species of the owl are noted, 

 together with the rook, Corvus frugilegus, the jackdaw, C. monedida, the jay, 

 C. glandarius, and the great cinereous sentinel Shrike, Lanius excuhitor, for 

 their destruction of cockchafers. A tawny owl, Strix aluco, Linn., was 

 once dissected at Berlin, and its stomach discovered to be full of insects, and 

 amongst these were at least seventy-five caterpillars of the Sphinx pinastri ; in 

 the destruction, as well, of field mice and rats they render services the importance 

 of which is but seldom recognised. The Bev. Gilbert White once watched 

 for a length of time a pair of Barn Owls, Strix jiammea, and noticed that 

 they brought a mouse to their nest, on an average every five minutes ; a 

 couple of the little owls carried to their young, eleven mice in the course of 

 an evening in the month of June. Nothing can be more absurb than the 

 way in which these birds are hunted down by ignorant rustics and plough- 

 men, whose chief delight is to have a few of them pilloried up against the 

 doors of farm-yard buildings, A great number of diurnal birds of prey, 

 such as the sparrow-hawk, Falco nisus, and the kite, Falco milvus, are mis- 

 chievous, for they slaughter indiscriminately the more diminutive useful birds 

 and even the smallest of their class devour as many birds as insects. Still 



