The Biology of the Crocodilia 25 
The complete process of incubation probably 
extends through a period of about eight weeks, 
but no accurate observations along this line could 
be made. For some hours previous to hatching 
the young alligators make a curious squeaking 
sound inside the shell, that may be heard for a 
distance of several yards: this sound may be for 
the purpose of attracting the attention of the female 
alligator, who will open the top of the nest in time 
to allow the just hatched alligators to escape: unless 
thus rescued, it would seem impossible for the little 
animals to dig their way out from the center of 
the closely packed mass of decaying vegetation. 
At the time of hatching the alligator is, as already 
noted, about eight inches in length, and it seems 
impossible that it should have been contained in 
so small an egg. 
The size of alligator eggs, as might be expected, 
is subject to considerable variation. In measuring 
the eggs a pair of brass calipers was used, and the 
long and short diameters of more than four hundred 
eggs were obtained. A number of eggs of average 
size, when weighed in mass on the scales of a 
country store, gave an average of 2.8 oz. per egg. 
There was more variation in the long diameter 
of eggs than in the short diameter. 
The longest egg of all those measured was 85 
mm.; the shortest was 65 mm. The widest egg 
(greatest short diameter) was 50 mm.; the nar- 
rowest egg (least short diameter) was 38 mm. 
