60 TRANSACTIONS, NATURAL HISTORY SOCIETY OF GLASGOW. 
proceeded to erect their own dome on the firm foundation laid by 
the unsuspecting blackbird. 
Some of the apple and pear-trees, which are trained along our 
garden wall, are favourite nesting-places for blackbirds and 
thrushes. After the nests have been completed and some eggs 
laid, they are frequently forsaken by the birds, probably, in many 
cases, through the latter having been captured by some cat in the 
course of her nocturnal wanderings. On such occasions, however, 
the cat usually springs on her prey, and the nest is either tilted to 
one side, or pulled out of shape, or shows other unmistakable 
signs of having been forcibly vacated by its tenant. On the other 
hand, the nest often remains apparently intact, but the eggs have 
little holes picked in them. For a long time I was unable to 
account for these holes in the eggs. They could scarcely have 
been caused by mice, as during the night time, when mice roam 
abroad, the parent bird always remains seated on her nest. From 
the destruction of the chaffinches’ eggs already referred to, and 
other facts which have since come under my notice, I am inclined 
to believe that the holes are picked by sparrows. As it is 
improbable that the latter feed on the eggs of other birds, their 
destruction of these is apparently the result of wanton jealousy or 
malicious mischief. 
At a meeting of the Society some years ago, it was stated that 
sparrows are in the habit of picking off the flowers of primroses, 
probably for the sake of the sweet deposit of nectar at the base 
of the corolla-tube. This had been repeatedly observed by several 
of the members who took part in the discussion, and it seems to 
be also practised by other birds of the finch tribe. In our garden 
much damage is caused to primroses, especially the rarer and more 
brightly-coloured varieties, by the flowers being picked off in this 
way ; but while I have never seen sparrows engaged in this work 
of destruction, I have often observed chaffinches picking off the 
primrose-flowers. As it is only within recent years that the birds 
have shown a liking for such floral sweets, the habit is probably 
an acquired one, common to several members of the finch tribe, 
and practised in some districts by sparrows, and in others by 
chaffinches, 
