THE CROSSBILL. 



Loxia curvirostra, Linnaeus. 

 Plate 17. 



The Crossbill is best known in England as an irregular visitor during the 

 autumn and winter months, often arriving in large flocks, and keeping more or less 

 to districts where there are woods of larch and pine. At times, however, the birds 

 remain and breed in suitable localities. 



In the northern parts of Scotland the Crossbill is resident throughout the year, 

 and it is also widely spread over Europe. 



The nest, begun very early in the year, is usually placed on the branch of a pine 

 or fir, and is built of twigs and lined with grass and wool. The four, occasionally 

 five, eggs are in ground colour whitish or pale greenish-blue, marked with different 

 shades of reddish-brown. 



The main food supply of the Crossbill consists of the seeds of the larch and 

 spruce fir, as well as berries, pips, and insects. 



The song is soft and low in tone, and the call-note, as the birds flit from tree to 

 tree, is sharp and clear. 



The points of the Crossbill's upper and lower mandibles are placed athwart 

 each other, in some individuals crossing to the right, in others to the left, and form 

 a well-adapted tool wherewith to open the cones and extract the seeds of conifers. 



According to Professor Newton {Dictionary of Birds, p. 115), the young "on 

 leaving the nest have not the tips of the bill crossed." 



Mr. Knox, in his Autumns on the Spey (pp. 34-35), has happily described the 

 actions of a flock of Crossbills as follows : " After close observation, I noticed that 

 they seldom attempted to operate upon a cone on the exact spot where it grew, 

 but after snapping one off from a slender terminal twig, each bird would hop or 

 fly to the central part of the branch, and in parrot-like fashion hold it in his foot, 

 but more frequently under it, as a hawk holds a small bird when in the act of 

 devouring it, and quickly inserting his bill between the scales, split them open by 

 means of that wonderful tool, and extract the seeds with the greatest facility. 

 Occasionally a cone would fall to the ground just as it was snapped off ; but, in 

 such a case, a fresh one was instantly selected, no further notice being taken of the 

 one that had dropped." 



The colour of the female is a yellowish-green, and the males, after moulting in 

 captivity, never regain their red plumage. 



A form of our Crossbill, distinguished by having a larger and stouter bill, and 

 known as the Parrot-Crossbill {Loxia pityopsittacus, Bechstein) has been obtained 

 in the British Islands. This is an inhabitant of the pine regions of Scandinavia 

 and the northern parts of Russia. 



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