1002 



ZOOLOGICAL SOCIETY BULLETIN 



the representatives of the other orders. 

 While the average lizard or snake attains 

 maturity in one or two years, a tortoise or 

 crocodilian may require five years or more, 

 according to conditions, be- 

 fore reaching the stage that 

 might be designated as a 

 young adult. 



SPECTACLED CAIMAN 

 The protruding eyelids determine its common name. 



From that point it continues to in- 

 crease steadily in size until it reaches maxi- 

 mum, adult dimensions. The latter period, 

 embracing a slower growth may cover from 

 five to ten years — possibly more; and the 

 reptile continues to survive to a surprising 

 age as compared with lizards and snakes. 

 Many of the theoretical assertions relating 

 to the slow growth of crocodilians result from 

 the observation of captive specimens under 

 conditions that stunt them, namely, lack of 

 sufficient sunlight, improper and vacillating 

 temperature, lack of exercise and poor food. 

 The average "pet" alligator is a suffering 

 illustration. It appears to remain indefinitely 

 the same size, or to grow at a rate that would 

 require an interminable period to attain 

 maturity. 



In addition to the tepid water, high tem- 

 perature of the building and moist atmos- 

 phere, the feeding of our crocodilians is a 

 matter regulated with thorough system. It 

 is very essential that they should receive 

 plenty of bone nourishment. Beef and 

 fish alone are insufficient to promote rapid 

 growth, or cause the animals to attain a 

 large size. Our very small crocodilians are 



given a diet of earthworms and min- 

 nows. Upon this they are kept for 

 several months, when dead mice are 

 occasionally given them. As soon as they 

 show an increase in size, the quantity and 

 >ulk of food is correspondingly increas- 

 ed. Earthworms are then excluded from the 

 menu, while small rodents are given frequent- 

 ly, in alternation with frogs, fish and scraps 

 of beef. Young rats and sparrows are soon 

 added to the list. 



It will be realized that this food produces 

 good bone development. The larger speci- 

 mens receive small hares, pigeons, and large 

 fish, all of which are entire. This food supply, 

 we are convinced, closely approaches the 

 diet of the wild reptile. The amount of food 

 consumed by our specimens is not as great as 

 might be imagined. Usually they are fed 

 twice a week, and at most three times a week. 

 The average wild example should fare fully 

 as well as this. If there is a scarcity of larger 

 food it may always resort to a fish diet, for 

 the waters of most of the bayous frequented 

 by crocodilians usually teem with finny 

 creatures. 



It is of interest to note our observations 

 to date of the growth of alligators hatched 

 and reared in the Reptile House: 



Hatched Length Weight 



Oct. 1900 8 ins. \% oz. 



Oct. 1901 2 ft. 6 ins. 3% lbs. 



Oct. 1903 3 ft. 9 ins. 14 lbs. 



Oct. 1906 6 ft. ins. 60 lbs. 



Oct. 1912 9 ft. 3 ins. 190 lbs. 



Except for the distinct difference in the 

 outline of the snout, the various crocodilians 

 look very much alike to the popular observer. 

 Among all there is the rough, plated armor 

 of the back, the dull, monotonous coloration, 

 and always the semi-aquatic habits. From 



