230 The Alligator and Its Allies 
immediate neighborhood of the yolk, seems to 
consist of a number of very thin concentric layers. 
It varies in color, in different eggs, from a pale 
yellowish white, its usual color, to a very decided 
green. 
As might be expected, no chalazze are present. 
The yolk is a spherical mass, of a pale yellow 
color, lying in the center of the white. Its di- 
ameter is so great that it lies very close to the shell 
around the lesser circumference of the egg, so that 
it is there covered by only a thin layer of white, 
and care must be taken in removing the shell from 
this region in order not to rupture the yolk. The 
yolk substance is quite fluid and is contained in a 
rather delicate vitelline membrane. 
The albumen and yolk of the crocodile’s egg, 
as described by Voeltzkow, differ from those of 
the alligator only in the color of the albumen, 
which in the crocodile is normally light green (78). 
As pointed out by Clarke, the position of the 
embryo upon the yolk is subject to some variation. 
During the earliest stages it may occur at the pole 
of the yolk nearest the side of the egg; later it may 
generally be found toward the end of the egg; 
and still later it shifts its position to the side of the 
egg. It is probable, as Clarke says, that the 
position at the end of the egg secures better pro- 
tection by the greater amount of white, at that 
point, between the yolk and the shell; while the 
later removal to the side of the egg, when the vascu- 
