THE FINCHES 87 



stand connected with a bird's outer garb may be discussed, more fitly, 

 hereafter, in relation to the Finch family as a whole. 



In addition to the evolutionary points above mentioned, we have 

 in one, at any rate, of several deviations from the more common type 

 of Loxia, concerning the specific or merely varietal value of each of 

 which there is, of course, the usual barren disputation (for, strangely 

 enough, this has not ceased with Darwin, though the whole essence of 

 such jangles has crumbled at his touch) we have, I say, in the parrot- 

 crossbill (Loxia pityopsittacus) an instructive illustration of varying 

 habit bringing with it varying form ; for it is perfectly evident that, 

 in this bird, we see the final or rather up-to-date result of certain 

 individuals of the common kind having come to eat the seeds of the 

 Scotch fir, as well as, and so, gradually, instead of, those of the larch 

 and spruce, which form the staple of the latter. As more strength was 

 needed to extract these, a stouter bill and larger body were gradually 

 acquired by those birds which delighted to do so, till, insensibly, and 

 almost without knowing it, they found themselves parrot-crossbills. 

 That each kind, now preferring its own tree, should stay, or go, where 

 this grew, was of course a necessity of the case, and thus a difference 

 in geographical distribution was added to that of habit and structure, 

 for the Scotch fir does not extend so far north as either the spruce 

 or larch. 1 



Here, then, we seem to see, pretty plainly, a process of bodily 

 modification following upon a mental one, for though certain cross- 

 bills, through having harder beaks, or more vigorous muscles to work 

 them, may have been led to attack the Scotch fir-cones as well as the 

 others, yet why, because of this, should they have come to prefer 

 the former, all being equally open to them ? Taste, however, being 

 capricious, that the change should have been founded upon the pre- 

 ference presents no difficulty. For myself, I have long played with 

 a theory, in regard to this, which I will now, at last, seriously bring 

 forward, namely, that the first crossbill of all who began to pay atten- 



1 See Seebohm, A History of British Birds. 



