FLIGHT OF BIRDS. 
319 
the winter, and thus furnish nourishment for the birds 
which arrive upon the melting- of the snow.* The 
snow bunting, moreover, feeds, as Temminck remarks, 
also on insects, and Wilson found their stomachs Med 
with shell lish. 
“ Fabricius,f and other writers, mention, that the male 
loudly serenades the female during incubation, but 
that his song ceases when the young are hatched. Sir 
George Mackenzie informs us, that the song is pleasing, 
and resembles the first three or four notes of the robin ; j 
whilst Marten, who, perhaps, was not musical, says, ‘ I 
can tell nothing of its singing, only that it whistleth 
a little, as birds use to do when they are hungry.’ 
Spitzb. p. 73.” — Richardson. 
GENUS IV. — COL UMBA. 
36. COLUMBA MIG BA TORI A. THE PASSENGER PIGEON. 
AUDUBON, PLATE LXII. 
The most important feature in the natural history of 
these birds is their migration. These migrations are 
caused by the necessity of providing for food, and, con- 
sequently, they do not take place at any fixed period or 
season of the year. Indeed it happens sometimes, that 
an abundant supply of food in one district, will keep 
these birds absent from another for years. 
Their great power of flight enables them to pass 
over vast tracts of country in a very short time. 
Pigeons, for example, have been killed in the neighbour- 
hood of New York, with their crops still filled with 
rice, collected by them in the fields of Georgia and 
Carolina, the nearest points at which this supply could 
possibly be obtained ; and as it is well ascertained, that, 
owing to their great power of digestion, they will 
decompose food entirely in twelve hours, they must 
* On their first arrival they generally feed on grass seeds ; but 
as the summer advances, they live much on worms, and are then 
not so much esteemed. — Hearne, l. c . 
•j' Fauna Grcenl. p. 119. 
| Travels in Iceland , p. 341. 
