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. 



