80. NOTES OX THE BIRDS OF lONA, 



may then be cut out with a spade; and the soi]^ though soft^ is so tenacious 

 that these blocks may all be returned to their places again; and the burrow 

 not being destroyed, is sometimes tenanted again next season. The birds 

 come to their holes in the first week in June; the eggs are laid by the first 

 week in July; and on the 13th. of October I have found the young very 

 recently hatched. I once kept a pair and succeeded in rearing one; the* 

 other one was killed by accident. They would take small pieces of fish very 

 readily, and were more active at night than during the day. The young 

 one when fully fledged differed from the adult merely in being of a rustier 

 black, and having an ill-defined white mark across the wing, formed by the 

 pale tips of the secondaries Both the young and the old ones, when con- 

 fined in a basket or bag, escape at the smallest aperture, climbing up the 

 sides like mice, in doing which they use their hooked bills to pull themselves 

 up with: it seems to be of more service to them than their claws. 



As might be expected from their great length of wing they cannot spring 

 up quickly into the air; when one is allowed to escape from the hand, he 

 runs rapidly along the ground for several yards with the wings in motion 

 before he can get fairly started; but if he meets with a declivity, he throws 

 himself off and swoops away to his ocean home. Within the limited space 

 of a room their wings are quite useless. 



The Petrel is also found breeding at Staffa, and at least one of the 

 Treshinish Islands, though I have no doubt they frequent all of them. Here 

 their nesting-places are very different from those at Soay, for they make 

 their nests under the large stones on the beach. These beaches ai-e com- 

 posed of blocks of basalt, about the size of a hat, and are considerably 

 raised above the sea level. They seem never to have been much exposed to 

 the action of the waves, for these large stones are rugged and angular, 

 consequently lying loosely together, easily allowing the mouse-like Petrel to 

 penetrate the numerous interstices, and to circulate freely a long way below 

 the surface, just as we see a wren, chased by a dog, taking refuge in a 

 dry-stone dike; and while the dog keeps watching the hole at which he 

 entered, in a moment the Wren hops out of the dike a gun-shot further on, 

 and chirps a feeble insult at his pursuer. It would be impossible ever to 

 discover the Petrel in such a situation as this, were it not for its betraying 

 itself, which it does in a very peculiar manner, especially about dusk, in the 

 evening, or at sunrise. If you happen to be upon one of these wild solitary 

 spots, you hear a most peculiar buzzing noise, not unlike that of a spinning 

 wheel, or a goat-sucker. It is not continuous, for at intervals of about ten 

 seconds it is broken by a sharp click. You soon find this music issues from 

 beneath your feet: guided by the sound you commence removing the heavy 

 stones; you are encouraged in your labour by hearing the sound nearer and 

 more distinct; sometimes it ceases, then re-commences; the noise and rolling 

 of the rocks seem to provoke the subterranean musician to renewed efforts, 

 until with a vigorous effort the last great stone is rooted out, and the 



