IXTRODUCTIOISr. 
liii 
bird that usually hatches but once in a season, be deprived of her nest, 
with the whole number of eggs which she would have laid that year, 
had she been successful in incubation, that she will again build, and deposit 
a second and even a third lot. I'his evidently proves the assertion, that the 
number of eggs laid in a season in some measure depends on the incli- 
nation of the individual. In all birds the rudiments of their eggs have 
existence before impregnation, and they may readily be discerned in a chain, 
or link of little yellowish knobs, covered by a fine medullary film in the 
ovary. But these rudiments, though in appearance they form a perfect 
egg, are never prolific, or produce an animal like the parent, until they 
have been fecundated. Of the chain of eggs in the ovary of the female 
bird, only a part in general is impregnated at the same time, according to 
the pre-established rule of nature as to the number usually laid by the 
species. Though sometimes the female produces more than her common 
number, and at other times less. The stimulant, whatever it be that 
causes the egg to increase in size, separates it from the common chain, 
and protrudes it into the uterus, frequently acts without the influence of 
the male ; and this accounts for the unimpregnated eggs often discovered 
in the nests of birds. From a defect in the parts of fecundation, she will 
sometimes, though rarely, deposit eggs of a smaller size, or different for- 
mation, or without the calcareous shell, in a thin vellum-like cover; or of 
monstrous disproportion, inclosing two yolks, and sometimes with two 
shells. In general, the eggs which the bird in a wild state lays, are pro- 
duced in daily succession ; so that the short period of twenty-four 
part of its outside ; in seven days the birds had re-lined the part left, and the female had deposited 
in it four eggs. This nest was also taken out, and in nine days more they had built a new one, 
distant nearly thirty feet from the former, and the female laid in it four eggs, which it hatched. 
I knew the nests of the four pair, and it should be remarked, that the eggs of each differed conside- 
rably from the others in their colours and markings ; in those of one pair the ground was a light grey, 
with, a few purplish spots, and very round ; of another quite white and elongated, and with many- 
brown spots : of the third> the egg was ivory white, with a few rufous spots, at the larger end, 
and the egg of the fourth was of a bluish cast, thickly beset with brown and ash-coloured spots. 
