SONG-BIRDS 185 



the under-surface. — The presence of a number of narrow canals or 

 borings in the sandy or clayey bank of a stream is always a sure 

 indication of the presence of a colony of Sand-Martins (Cotyle riparia). 

 The birds construct these canals by means of their beaks, which, though 

 short, are very sharp and hard. The tubes are often over 6 feet long, 

 and widen out at their ends into a terminal breeding-chamber, or nest 

 proper. The bird is easily recognised by the brownish-grey colours of 

 the upper side and the white colour of the under surface, which is marked 

 by a grey transverse band. 



Family 4 : Warblers (Sylviidae). 



The Nightingale (Luscinia philomela). 



(Length 6| inches.) 



The nightingale returns to its nest of the previous year at the second 

 half of April at a time when trees and bushes have not yet acquired their 

 full dress of green. It is then that the inconspicuous plumage of this 

 bird, resembling the colour of bark (upper side rufous, under surface 

 light grey), provides an excellent protection against its numerous enemies. 

 Even later, when earth has fully resumed its green garment, the 

 nightingale for the same reason is only with difficulty to be distinguished 

 among its surroundings. We can hear its song, but the bird is generally 

 discovered only after a prolonged search. On the ground, especially 

 when this is covered with dry leaves, the brown dress renders the bird 

 quite invisible. (The nightingale has been termed a confiding bird, 

 because it allows one to approach near to it. Does it not rather deserve 

 to be called a bold bird ? Compare, on the other hand, the golden oriole.) 

 As it collects its food mostly from the ground (worms, insect larvas, 

 smooth-skinned caterpillars), it frequents dense bushes in gardens and 

 parks, or the underwoods in the clearings of leafy forests. It also likes 

 the neighbourhood of ponds and streams, where there is always an 

 abundance of insect food, and where it can drink and bathe. The 

 beak is awl-shaped, and of just sufficient strength and hardness for 

 picking up the soft food. (Compare, on the other hand, the beak of 

 finches.) The bristle-like feathers at the base of the beak act as tactile 

 organs in rummaging among dry leaves. (Compare with the moustache 

 hairs of mammals.) The long, strong legs enable the bird to hop along 

 the ground or hold on to branches for prolonged periods. (Compare, on 

 the other hand, the swallow.) The roughly-constructed nest is placed on 

 the ground, or in the branches of the underwood, and invariably upon a 

 foundation of dry foliage, so that it bears the closest possible resemblance 



