46' 



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13 



on weather; for the four eggs taken in the unusually mild spring of the present year (1872) were 

 obtained as late as the 27th of April. It is impossible to say with any degree of certainty if the 

 Nutcracker breeds twice in the year ; but I do not think it improbable, as a forester on Bornholm, 

 who knows the habits of this bird well, assures me that he has seen old birds feeding their 

 j oung as late as September. In number the eggs vary from three to five ; for we found one nest 

 containing three eggs, incubated, four containing four, and three containing five eggs ; and it has 

 been noted, from those nests which were discovered when the bird had commenced laying, that 

 she deposits one daily. 



" In size the eggs vary from 32 by 24 millimetres to 34 by 26 and 35 by 25 millimetres, the 

 normal size being 33-5 by 24 - 5 millimetres. From this it will be seen that the egg of the 

 Nutcracker rather exceeds those of Perisoreus infaustus and Turdus viscivorus in size, but is 

 smaller than the egg of the Magpie. They are oval in form, scarcely tapering towards the small 

 end ; the grain of the shell is very fine, about as in eggs of Totanus glareola, and is composed 

 of round grains which, under the microscope, show a few warty elevations, which are found 

 more especially at the ends, there being more at the small end ; these warts are seldom elongated 

 in shape, and are isolated in position, not run together in a network as, for instance, in eggs of 

 Garrulus glandarius. I have not found in any the long furrows which are clearly visible in 

 eggs of the Magpie and other corvine birds. The pores in the shell are very fine, and evenly 

 distributed over the surface, which is smooth and polished like a piece of cream-laid paper. 

 Like all thin-shelled eggs, when first blown they are clear, but get afterwards duller; the 

 ground-colour is pale whity blue, just washed with greenish, but varies somewhat in tone. As 

 regards the markings, it was impossible to distinguish between shell- and surface-spots in the 

 eggs we first found, as the thinly scattered isolated dots looked merely like bright-coloured shell- 

 spots ; but in several of the eggs found later on, the shell- and surface-spots were clearly distin- 

 guishable. Both shell- and surface-markings consist of fine dots and spots, which vary greatly 

 in number, as some eggs are almost unspotted, though never without a few fine clots, very pale 

 in tinge, whereas others are strongly marked with spots, like light-coloured eggs of Perisoreus 

 infaustus; but these spots are always evenly distributed over the entire surface of the shell: 

 the spots vary in size, from the minutest dot to a blotch nearly 3 millimetres in diameter ; but 

 the normal size is about - 5 to 1 millimetre. The underlying shell-spots are in colour dirty 

 grey, sometimes tinged with violet, and are often very faint in tinge. The surface-markings are 

 greyish brown, and much richer in tone than the shell-markings. In the eggs taken this year 

 (1872) the surface-spots are on the shell-spots; thus the eggs have double markings, not 

 observed in those previously taken. And I may further remark that the markings vary in eggs 

 out of the same sitting, as one of those last taken was very strongly marked, the others being 

 much less spotted, which arises, I believe, from the supply of colouring-matter becoming less 

 after depositing one or two eggs : thus the one first deposited will be coloured brightest, and the 

 remainder will be paler, according to the order in which they are laid. In the inside the eggs 

 usually appear to be light green, owing to the colour of the shell shining through ; but when the 

 inside skin is thick they appear almost white. The yelk is light yellow, and the white of the egg 

 clear and colourless. So far as my experience goes, the egg of the Nutcracker can only be mis- 

 taken for those of two other species, viz. that of Perisoreus infaustus, which, however, is smaller, 



