320 
ORDERS OF REPTILES— CROCODILES AND ALLIGATORS 
duce by laying from thirty to sixty oblong, per- 
fectly white eggs, in layers, in a low mound of 
muck, or vegetable mould, or sand. The female 
lies in wait to defend her eggs while they hatch 
through the heat of the sun, or by regular fer- 
mentation. From the nest of the salt-water 
crocodile I have taken fifty-five eggs, from the 
gavial, forty-one and forty-four, from the Florida 
crocodile, twenty-six, and from the alligator, 
thirty-eight. The nest of the alligator is about 
two feet high and four feet in diameter. 
At birth, young alligators are about eight 
inches long. As soon as they are out of the 
shell, they are wide-eyed and alert, and ready to 
take to the water. At this period, the muzzle is 
short, abnormally broad, and the arch of the 
forehead very high. 
Growth and Size. — In the Reptile House of 
the New York Zoological Park, we have recorded 
the following facts regarding the rate of growth 
of our alligators: 
Inches. 
Weight. 
hatched, 
8 
If oz. 
one year old, 
IS 
9f “ 
22 months old, 
23 
3 lbs. 
29 
45 
14 “ 
An alligator when received measured 6 ft . 1 1 in. 
During the first year it grew 1 ft. 
3 in. and measured 8“ 2“ 
During the second year it grew 1 ft. 
1^ in., and measured 9 “ 3 “ 
During the third year it grew 1 ft. 
7 in. and measured 10 “ 11 “ 
Length of “Old Mose,” July, 1899, 12 feet. 
Length of “Old Mose,” July, 1903, 12 feet 5 in. 
Judging by the rate of growth of specimens of 
all sizes under constant observation in the Zoo- 
logical Park, where they probably are growing 
as rapidly as they could in a wild state, I have 
reached the conclusion that, under ordinary 
circumstances, a wild crocodile or alligator is 
about ten years in attaining a length of twelve 
feet. The average rate of growth up to twelve 
feet appears to be about 1.4 inches per month. 
After twelve feet has been attained the rate is 
much slower, being (in the case of our largest 
specimen) about two inches per year. 
The secret in securing rapid growth in captive 
crocodilians lies in giving them a pool four feet 
deep, of water warmed to a temperature of be- 
tween 80 and 90 degrees F. If kept in cold water, 
and but little of it, they are uncomfortable, they 
feed sparingly, and grow either very slowly, or 
not at all. 
AMERICAN SPECIES OF CROCODIL- 
IANS. 
The Florida Crocodile 1 is the type which 
represents the midway average between the two 
extremes of the crocodilian series, — narrow- 
beaked gavial and broad-snouted alligator. It is 
a subspecies of the so-called “American” croco- 
dile ( Crocodilus acutus), of Central and South 
America, and is not found elsewhere than in 
southern Florida. It is the only crocodile which 
inhabits a country that is visited by killing 
frosts. 
The presence of a true crocodile in Florida was 
not discovered until 1875, when a pair of speci- 
mens of large size were collected in Arch Creek, 
at the head of Biscayne Bay, by Mr. C. E. Jack- 
son and the writer. The male measured 14 feet 
2 inches (with 4 inches of his tail missing), and 
the female 10 feet 8 inches. Since that date, at 
least seventy specimens have been taken be- 
tween Lake Worth and Cape Sable. Lake 
Worth is the northern limit of the species, but 
it is most abundant in the watery labyrinth of 
low land and shallow water where the mainland 
of Florida reluctantly sinks into the Gulf. 
The alleged “big ’gator” of Arch Creek was 
very wary, and permitted no boat to approach 
within rifle-shot. Even a boat completely masked 
by green branches, and innocently floating with 
the current, was enough to send the old fellow 
quickly sliding from his basking-place on the bank 
into deep water. At last, however, we shot him 
from an ambush in the mangroves opposite his 
mid-day lair, and secured him. His mounted 
skin is now to be seen in the United States Na- 
tional Museum. 
The adult male Florida Crocodile is very rough, 
externally, and usually its natural colors have 
been so far obliterated by age and exposure that 
on its upper surfaces its color is a dull, weather- 
beaten gray. The females, and males under 
eleven feet, are of a clean, grayish-olive color, — 
or dull yellowish-green, — very different indeed 
1 Cro-co-di'lus a-cu'tus flor-i-dan'us. 
