INTRODUCTION. 
9 
the Thrush, the Blackbird, and the Nightingale of Europe, preemi- 
nent for song, are all of the plainest colors and weakest tints. 
The natural tones of birds, setting aside those derived from edu- 
cation, express the various modifications of their wants and passions} 
they change even according to the different times and circumstances. 
The females are much more silent than the males; they have cries 
of pain or fear, murmurs of inquietude or solicitude, especially for 
their young ; but song is generally withheld from them. The song 
of the male is inspired by tender emotion, he chants his affectionate 
lay with a sonorous voice, and the female replies in feeble accents. 
The Nightingale, when he first arrives in the spring, without his 
mate, is silent; he begins his lay in low, faultering, and unfrequent 
airs ; and it is not until his consort sits on her eggs, that his en- 
chanting melody is complete ; he then tries to relieve and amuse 
her tedious hours of incubation, and warbles more pathetically and 
variably his amorous and soothing tale. In a state of nature this 
propensity for song only continues through the breeding season, for 
after that period it either entirely ceases, becomes enfeebled, or loses 
its sweetness. 
Conjugal fidelity and parental affection are among the most con- 
spicuous traits of the feathered tribes. The pair unite their labors 
in preparing for the accommodation of their expected progeny ; and 
during the time of incubation, their participation of the same cares 
and solicitudes continually augments their mutual attachment. 
When the young appear, a new source of care and pleasure opens 
to them, still strengthening the ties of affection; and the tender 
charge of rearing and defending their infant brood requires the 
joint attention of both parents. The warmth of first affection is thus 
succeeded by calm and steady attachment, which by degrees ex- 
tends, without suffering any diminution, to the rising branches of 
the family. 
This conjugal union, in the rapacious tribe of birds, the Eagles 
and Hawks, as well as with the Ravens and Crows, continues com- 
monly through life. Among many other kinds it is also of long endur- 
ance, as we may perceive in our common Pewee and the Blue-bird, 
who year after year continue to frequent and build in the same cave, 
box, or hole in the decayed orchard tree. But, in general, this asso- 
ciation of the sexes expires with the season, after it has completed 
the intentions of reproduction, in the preservation and rearing of 
the offspring. The appearance even of sexual distinction, often 
vanishes in the autumn, when both the parents and their young are 
