162 SWALLOWS NIGHTINGALES. 



Sand-martens differ from their congeners in the diminutive- 

 ness of their size, and in their colour, which is what is usually 

 called a mouse-colour. Near Valencia, in Spain, they are 

 taken, says Willoughby, and sold in the markets for the table, 

 and are called by the country people, probably from their 

 desultory, jerking manner of flight, Papillon de Montagna.* 



LETTER LX. 



TO THOMAS PENNANT, ESQ. 



SELBORNE, September 2, 1774. 



DEAR SIR, Before your letter arrived, and of my own 

 accord, I had been remarking and comparing the tails of the 

 male and female swallow, and this ere any young broods 

 appeared ; so that there was no danger of confounding the 

 dams with their pulli ; and, besides, as they were then always 

 in pairs, and busied in the employ of nidification, there could 

 be no room for mistaking the sexes, nor the individuals of 

 different chimneys, the one for the other. From all my obser- 

 vations, it constantly appeared that each sex has the long 

 feathers in its tail that give it that forked shape ; with this 

 difference, that they are longer in the tail of the male than in 

 that of the female. 



Nightingales, when their young first come abroad, and are 

 helpless, make a plaintive and a jarring noise ; and also a 

 snapping or cracking, pursuing people along the hedges as 

 they walk : these last sounds seem intended for menace and 

 defiance, f 



* Dr Richardson considers the sand-marten of the fur countries of 

 North America, as identical with the European bird ; and, from all 

 accounts, it is the same in every quarter of the glohe. It breeds but once 

 in the fur countries, generally late, and takes its departure about the 

 middle of August with the rest of the swallow tribe ; which confirms 

 the fact that they live in societies. That traveller says, " We observed 

 thousands of these sand-martens fluttering at the entrance of their burrows, 

 near the mouth of the Mackenzie, in the sixty-eighth parallel, on the 4th 

 July ; and it is probable, from the state of the weather, that they had 

 arrived at least a fortnight prior to that date. They are equally numerous 

 in every district of the fur countries, wherein banks suitable for burrowing 

 exist." En. 



f It has been generally believed that the migratory songsters, both old 

 and young, return to their native haunts in the breeding season. From 

 this circumstance it is believed, that if any of these could be bred beyond 

 the ordinary limits of their incubation, they would return in the follow- 

 ing season to their birth place. Impressed with this belief, Sir John 



