196 THE TITS 



apple, and oak-trees in the immediate neighbourhood of the nest. 

 Those collected from the fruit-trees were chiefly larvse of the winter 

 moth (C. brumata), and those from the oak-tree mottled umber moth 

 (//. defoliaria). Usually one caterpillar was brought to the young 

 on each occasion, and often four visits were made in the course of 

 five minutes. If we take the average number of visits at the rate of 

 twenty-four per hour for sixteen hours, representing one working day, 

 this gives us a total of 384 visits per day ; and if twenty days are 

 occupied in rearing the young, this gives us a grand total of 7680 

 visits to the nest during this period, so that the single pair of birds 

 would be responsible for the destruction of between 7000 and 8000 

 insects, chiefly caterpillars " (p. 33). 



Personally, I would estimate the number of insects destroyed by 

 one pair of great or blue-tits at even a higher rate, because the young 

 are with their parents, and fed on insect food after the average three 

 weeks assigned to the nestling period. At this stage in their growth 

 they require a large amount of food, and for some ten days longer, 

 while a glimmer of light remains in the sky, the indefatigable 

 parents may be seen feeding their half-grown brood as late as 9.45 

 or 10 P.M. 



Both great-tits and blue-tits will hawk for insects on the wing, but 

 perhaps the latter bird shows greater dexterity as an amateur fly- 

 catcher, than does his more heavily built relative. 



When we take into consideration the enormous amount of good 

 the various species of Tits undoubtedly do, it is not to be wondered 

 at that so far back as 1873 the International Economic Congress, held 

 at Vienna, placed eight species of Titmice on the list of useful birds 

 to be protected. This Congress was the direct outcome of a move- 

 ment set on foot by the German farmers earlier still in 1868 when 

 they complained of "the excessive injury done by insects, owing to 

 the sensible decrease and disappearance of birds." 



Boards of Agriculture, whether British or foreign, do not as 

 a rule publish sentimental pamphlets for women to weep over, but 



