268 SCIENCE FROM AN EASY CHAIR 



temperate climates. There are Spanish, African, Italian 

 and Indian species, closely related to the common house- 

 sparrow, which I should like to see put out side by side 

 with it and some of its varieties for the public edification 

 in the Natural History Museum. These are the true 

 " sparrows," and should be compared side by side with 

 the hedge-sparrow, and the differences pointed out. 



There is another true sparrow in England, called the 

 " tree-sparrow," which is not nearly so common as the 

 house-sparrow. They are, however, so closely allied to 

 one another that hybrids have been produced between 

 the two. On the other hand, the hedge-sparrow is a 

 great deal too remote from the finches to interbreed 

 with the house-sparrow or any other of the finch group. 



There ought to be a careful report on the probable 

 effects, in every direction, of a great destruction of house- 

 sparrows before any very drastic measures are taken in 

 that direction. The employers of gamekeepers should 

 remember that by destroying owls, hawks, and weasels 

 they may not only enable small injurious birds to flourish 

 in excess, but that they may encourage disease and weak- 

 ness in the game-birds which they so eagerly desire to 

 multiply, since the natural extermination of weakly birds 

 by birds and animals of prey is put an end to when the 

 latter are abolished. In all such matters more knowledge 

 is needed, and reasonable people will not take irretriev- 

 able action until they have taken the trouble to obtain 

 thorough knowledge. 



It is a curious fact that though the house-sparrow does 

 not naturally sing, yet hand-reared house-sparrows have 

 been made, by association with bull-finches, to acquire the 

 song of that bird a truly astonishing instance of hidden 

 or latent capacity. 



A lover of trout-fishing has been writing lately upon 

 the question as to whether the trout in much-fished rivers 



