330 THE STRUCTURE AND LIFE OF BIRDS CHAP. 
end of his tether. In South America there is a little 
bird (Furnarius cunicularius) which makes its nest 
in a horizontal burrow in the ground, said to be often 
nearly six feet long. These birds have been known 
to burrow again and again into a mud wall with a 
view to nesting there, and were no doubt surprised 
when they came to daylight on the other side. 
Yet they had flown over the wall, and had had many 
opportunities of seeing its small thickness before 
they set to work! In the same way with a stupid 
persistence one of Mrs. Brightwen’s pet starlings 
continued to search for grubs in every corner of the 
drawing-room. The intelligence, however, comes 
oftener to our notice than the stupidity. 
Song. 
Daines Barrington took three Linnets, when quite 
young, from the nest, and put them with different 
foster-mothers, selecting three with casily recognis- 
able notes—the Skylark, the Woodlark, and Titlark or 
Meadow Pipit—-and each, he maintained, learnt and 
adhered to the song which it heard in the days of its 
early youth. “The Linnet educated by the Titlark was 
afterwards put with other Linnets, but it never unlearnt 
the Titlark song. Daines Barrington was one of the 
correspondents of Gilbert White, of Selborne, and 
these experiments were made in the latter half of 
the last century. More recent investigators have 
not, as a rule, been led to the same conclusion. Mr. 
1 See Darwin’s Journal of Researches (Minerva Library 
edition), p. 69. 
