MIGRATION OF SWALLOWS. 
295 
recurs, — what is the peculiarity of economy which leads 
One species of bird to conceal its nest with the most 
extraordinary care and address, and another to place its 
offspring- in the most exposed situation it can select ?” — 
Richardson. 
18 . uinvNno fvlfa , vieill. 
THE REPUBLICAN, OR CLIFF SWALLOW. 
AUDUBON, PLATE LXVIII. 
In his account of this species, Audubon has the fol- 
lowing observations on the migration of swallows : — 
« £einn' extremely desirous of settling the long agitated 
luestion respecting the migration, or supposed torpidity 
of swallows, I embraced every opportunity of examining 
their habits, carefully noted their arrival and disappear- 
ance, and recorded every tact connected with their 
history. After some years of constant observation and 
reflection, I remarked, that among all the species of 
Oiigratorv birds, those that remove farthest, from us, 
depart sooner than those which retire only to the 
coniines of the United States ; aud, by a parity of 
reasoning, those that remain later return earlier in the 
Spring. These remarks were confirmed, as 1 advanced 
towards the southwest, on the approach of winter ; 
for 1 there found numbers of warblers, thrushes, &c. in 
full feather and song. It was also remarked, that the 
Hirundo viridis of Wilson, (called by the Trench of 
Lower Louisiana, Le Petit Martinet a ventre blanch) 
remained about the city of New Orleans latei than any 
other swallow. As immense numbers of them were 
Seen during the month of November, l kept a diary ot 
the temperature from the third of that month, until the 
arrival of Hirundo purpurea. The following notes are 
taken from my journal ; and as I had excellent oppor- 
tunities, during a residence of many years in that 
country, of visiting the lakes to which these swallows 
Were said to resort, during the transient frosts, I present 
them with confidence? 
« November 11 . — Weather very sharp, with a heavy 
white frost. Swallows in abundance during the whole 
