THE POULTRY BOOK. 
Ill 
of the air-cell at the larger end. If this assertion he founded on fact it would 
enable us to make such a selection of eggs for hatching as would present us with 
chickens of either sex according to our will. The instructions given by 
Columella direct us to “ select the round eggs, for they contain female birds, and 
reject the oblong-shaped, for they contain birds of the opposite sex.” Again : 
‘‘By the position of the air-cell at the butt end of the egg, those may be selected 
which will produce the male sex; in these the air-cell is in the centre of the end. 
If the cell be a little on one side, the egg will produce a female chick. The 
position of the air-cell is easily discovered by holding the egg betv^een the eye and 
the light.” But, if the round egg, which, according to the first theory, should 
produce a pullet, have the air-cell in the centre of the end, it ought, according to 
the second, to produce a male chick ; while, on the other hand, the oblong- shaped 
egg may have the air-cell on one side, and therefore the inmate should be of the 
feminine gender. It is obvious that these tests are contradictory, and we have 
only to remember that as little, if any, variation is ever found in the shape of the 
eggs of' any one hen, it ought to follovr that the produce should invariably be of 
one sex, which is never the case ; we are, therefore, not inclined to believe in the 
opinion advocated by Columella and his followers. 
Eespecting these erroneous ideas that have been thus placed before the public, 
with regard to the possibility of judging beforehand of the sex of eggs, from their 
shape or the position of the air-vesicle, a slight acquaintance with the anatomy 
and physiology of the fowl would disprove the truth of the statement. The germ 
of the future bird is formed with the yolk in the ovary ; and as the latter passes 
along the egg-passage — a tube upwards of two feet in length — it merely receives in 
its progress the white, the two layers of membrane which enclose the air-cell 
between them, and lastly the shell, these being formed or secreted by different 
parts of the canal. It is evident that the air-cell is not formed until after 
the white and the inner of the two membranes is completed, and can there- 
fore'have no influence upon the germ. The shape of the egg, moreover, entirely 
depends on the shell, which is the last part formed ; and as the germ in the yolk 
is already completed it is exceedingly improbable that the one can have any con- 
nection whatever with the other. Perhaps the best reply to this absurd theory is 
that it has been repeatedly disproved by the most careful experiments. 
It will not be found desirable to hatch Spanish chickens at a very early period of 
the year, unless they are designed for exhibition at the Autumn Chicken Shows. 
The end of April is quite soon enough for them to make their appearance, and 
those birds that are not hatched till May will eventually be found to make the 
finest specimens. If produced too early in the year the young birds suffer from 
cold, as they are much longer in fledging than most other breeds. The young 
when first hatched are clothed in black down, marked with a certain proportion of 
white on the fore part of the body ; this, however, is followed by the same black 
plumage as the darker portion. During the growth of the feathers it is ex- 
ceedingly important that the birds should be well fed, for not only has the growth 
