INCUBATION AND AGE OF BIRDS.


The full period of incubation by the hen in this country, is well known
to be twenty-one days. In warmer climates it is said to be a day or two
less. The periods of incubation vary much in different species of birds.
We introduce the following table, which has been compiled from different
authors by Count Morozzo, in a letter from him to Lacepepe, to show the
periods of incubation compared with those of the life of certain birds.

Names of | Periods | Duration |
Birds. | of Incu- | of | Authority
| bation | Life. |
------------+----------+-------------+--------------------------
| Days. | Years. |
------------+----------+-------------+--------------------------
Swan | 42 | About 200 | Aldrovande
Parrot | 40 | About 100 | Wulmaer
Goose | 30 | 80 or more | Willoughby
Eagle | 30 } | Period of |
Bustard | 30 } | life not |
Duck | 30 } | known. |
Turkey | 30 } | |
Peacock | 26 to 27 | 25 to 28 | Aristot. & Pliny
Pheasant | 20 to 25 | 18 to 20 | A Treatise on Pheasants
Crow | 20 | 100 or more | Hesiod
Nightingale | 19 to 20 | 17 to 18 | Buffon
Hen | 18 to 19 | 16 to 18 | Buffon