I 39 I 
twenty-six fully formtd eggSt each about two inches in diameter. 
Its shell measures 17 inches in length- On Singapore island 
four species of Tortoises ocqut : The largest, but rarest of them, 
is the Catiagur pkta which is easily distinguished by its red 
nose. The shell of the largest specimen in the Museum 
measures l%% inches.— Next in size comes the Flat-backed 
Tortoise (Cyciemys platynoia) which is found in a little stream 
near Selitar, also in the brooks leading to the Impounding 
Reservoir and elsewhere. A very pretty species which is fairly 
common on Bukit Timah, is the Spiny Tortoise (Geoemyda 
spinosa). The spines along the margin of the shell are most 
marked in young specimens. Lastly there is the Box Tortoise 
(Cyciemys ambohieHsis). It has a smooth black upper shell and 
two yellow stripes along the neck. The lower shell has a 
transverse hinge so that it can be closed tightly against the 
upper one. It is common in swamps and paddy fields. The 
Malay name is *tongtong* or * tuntong.* 
CROCODILES. 
The Crocodiles of the world consist of three families, the 
true Crocodiles, the Gavials and the Alligators- Of these only 
the first two families are found in the Malay region, whilst the 
Alligators, with one exception, are restricted to the New World. 
However, Singapore people very frequently speak of ' Alliga- 
tors ' as occurring here, the same way as they say with 
preference * Boa constrictor * instead of Python, * Iguana ' 
instead of Monitor, and ' Chainaeleon ' when they mean the 
green lizard Calotes. 
The external differences between Crocodiles and Alliga- 
tors may be briefly stated as follows: In Crocodiles the fourth 
tooth of the lower jaw is very large and fits into a distinct notch 
or indentation at the margin of the upper jaw ; they have 
fourteen to fifteen teeth in each half of the lower jaw; they 
have horny shields on the upper surface only, and their hind 
feet are completely webbed. 
In Alligator* the margin of the upper jaw is not indented, 
and the fourth lower tooth merely fits into a pit ; they have 
seventeen to twenty-two teeth in the lower jaw ; they have 
horny shields on the lower surface as well as on the upper one, 
and their hind feet are incompletely webbed. 
Crocodiles and Gavials, however, can be distinguished at 
the first glance. It is impossible to confuse the long narrow 
snout of the latter with the broad triangular head of the former. 
