16 
it is all-important with regard to our birds, particularly those that 
are stationary. Itis well known that species which have lived long 
on au 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, com- 
pared with continental examples. The Blackcock of Norway and 
Switzerland will be found to have the tone of its plumage more inten- 
sified 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 
Longtailed Tit (Mecistura caudata) of Norway and Denmark differs in 
having a white head, while that of Great Britain has the crown and 
face dark or obscurely striped; and the Cole Tit (Parus 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 specific distinetion, 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 [am strengthened in this view by noting that 
among such groups as the 7’rochilide, or Humming-birds of Ame- 
rica, 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 Phasianus 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 im- 
portant result. We see this intercrossing carried to a still greater 
extent in our domesticated Pigeons and Fowls; but beyond the 
acquisition of certain variationsin 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 advantages likely to accrue from the 
interbreeding of our Grouse with that of Norway (Tetrao salicet?). 
Ornithologists are questioning whether these are not one and the 
same species, and if the differences existing between the two may not 
be due to the influence of climate, Should such be the case (and I. 
think it probable), then the introduction of the original stock would 
doubtless effect an improvement 7n the health and vigour of our birds. 
Prof. Rasch, of Christiania, believes the two so-called species to be 
identical, and is introducing our Grouse into his country, partly to 
determine this point, and partly for the sake of the infusion of fresh 
