154 NEW YORK ZOOLOGICAL SOCIETY. 



they are indifferent to the presence of sunlight, provided the tem- 

 perature is high. Between 75 and 85 F. constitutes a tempera- 

 ture in which Lacertilians flourish. The omnivorous species 

 evince a like disposition, but eventually die of enteritis. 



The most delicate of the lizards are the insectivorous forms, 

 and the vast majority of them require a continued flood of sun- 

 shine during the day to awaken them to activity and appetite. In 

 a wild condition these smaller lizards seek the sun from the time 

 its rays first strike the ground until it sinks among the trees. To 

 these active, diurnal creatures the sun is one of the most important 

 factors of life. Without its light they are dull and sluggish, no 

 matter what the degree of temperature. Thus it is that these 

 creatures of the light are difficult to maintain in captivity. Some 

 are more hardy than others, but captive quarters can at best be 

 but a poor imitation of their natural haunts. During the few 

 hours that sunlight streams into their cages they lie flattened 

 on the sand or boughs, drinking in the warm light, and so 

 greatly enjoying the abbreviated pleasure that often they fail to 

 feed properly. The wild insectivorous lizard hunts most of the 

 day, and under normal conditions consumes daily a large quantity 

 of food. Its activity demands this, and the feeding of an inactive 

 captive specimen slowly but steadily produces enervation. The 

 creature survives for a time, but eventually succumbs to malnu- 

 trition, brought about by a lack of variety in its insect food. Dur- 

 ing the few hours of light and activity, the food is gorged hastily, 

 and the alternate sluggish condition of the reptile, when the 

 sunlight has gone, produces imperfect action of the digestive ap- 

 paratus. Such insectivorous species as the Anguida or snake- 

 like lizards, which care not so much for the sunlight as to bur- 

 row after their prey, thrive for many years in captivity. 



As captives the larger lizards become very tame, and show 

 considerable intelligence, although their interest seems invariably 

 associated with appetite. Whenever their cage doors are opened 

 the monitors in our Reptile House always approach them and 

 nose about their keeper, with their long, forked tongues playing 

 at frequent intervals. Frequently they will climb over the keep- 

 ers' back and shoulders, in good-natured curiosity. The sight of a 

 rat or bird throws them into a frenzy, and they take such objects 

 from the keeper's hand with a display of ferocity that is quite 

 startling compared with their former quiet demeanor. 



Outside sunlight and air have a remarkable effect upon these 

 "tame" reptiles. During the past summer it was decided to place 

 the monitors in a large cage outside the Reptile House, that they 

 might enjoy the sun. The largest specimen, a Ceylonese mon- 



