XVI 
INTRODUCTION. 
on our moors, and the Ortyx virginiatms, or American Partridge, in our fields and coverts ; but what good 
woidd he efifected tliereby ? the Prairie-Hen would but disjdace a better bird, the common Grouse ; and the 
little Partridge would he no improvement upon our familiar species. There is no fear, however, that this 
will ever be accomplished ; and the sooner such fallacies are ended the better. It would be far wiser were 
the eflbrts of our well-meaning patrons of acclimatization directed rather to that interchange of blood among 
the same species which is essential to the maintenance of a healthy stock. I am sure it is all-important with 
regard to our birds, particularly those that are stationary. It is well known that species which have lived 
long on an island without a sufficient interchange will diminish both in size and brilliancy of tints : and 
hence, perhaps, may be explained the smaller size and more subdued colouring of many of our birds, 
compared with continental examples. The Blackcock of Norway and Switzerland will be found to have the 
tone of its plumage more intensified than those inhabiting Scotland, the black being unmistakably of a darker 
hue, and the gloss of the feathers more resplendent. The Norwegian Ptarmigan, too, is of a purer white 
compared with our own bird, while its full summer dress is much darker. So, again, the Long-tailed Tit 
{JS'lecistura caudatd) of Norway and Denmark dilfers in having a white head, while that of Great Britain has 
the crown and face dark or obscurely striped ; and the Cole Tit {Icarus ater) of Belgium in having the back- 
grey, instead of the slight olive tint seen in British examples. To make such differences, however, grounds 
for sj)eclfic distinction, as has in some cases been done, is in my opinion playing with science. That the 
drier and more rarified air of the Continent, coupled with the more direct influence of the solar rays, 
contributes to cause these slight differences, seems to me highly probable; and I am strengthened in this 
view by noticing that, among such groups as the Trochtlidoe or Humming-birds of America, some of the 
richest and finest colours are seen in species that frequent lofty situations. 
Most of the Pheasants now spread over every county of the British Islands are mongrels, brought about 
by the interbreeding of three kinds ; and their progeny are but too often rickety and sickly creatures. Those 
of our sportsmen who have flushed a true Phastanm torquatus in England, or killed the same bird in China- 
Its native country, must have been astonished at the quickness of its arrow-like flight, and the wildness of its 
actions. 
The scientific naturalist, of course, repudiates all varieties such as the Pheasants alluded to, no two of 
which are alike in colour or markings, and whose promiscuous interbreeding can lead to no important 
result. We see this intercrossing carried to a still greater extent in our domesticated Pigeons and Fowls ; 
but beyond the acquisition of certain variations in plumage, or of qualities rendering them more highly 
esteemed for the table, nothing of interest is attained. 
Whilst on the subject of interbreeding, I should wish to draw the attention of sportsmen to the advan- 
