138 'Journal of Cotuparative Neurology and Psychology. 



perching high on the backs of the larger ones. Every member of 

 these groups is on the alert and, at the slightest indication of 

 danger, there is a general scramble for the water. The imitative 

 instinct seems to be highly developed. If one animal scents 

 danger and topples over into the water his neighbors quickly 

 follow suit. I have seen all the tortoises within a hundred yards 

 of shore line follow the lead of one that had become alarmed. 

 So acute is their sense of danger that almost any slight divergence 

 from normal conditions serves to give the alarm. A startled bird 

 flying from the grass along the shore or a frog jumping into the 

 water is sufficient cause for a general commotion among the 

 basking tortoises. 



By concealing myself in the long grass across the lagoon from a 

 favorite basking place, I was able to note their behavior. After 

 the initial alarm caused by my approach, they regained confi- 

 dence and cautiously came to the surface. After reconnoitering 

 carefully and seeing nothing suspicious, they proceeded to crawl 

 out upon the narrow ledge where they habitually congregated. 

 One after another they crawled out, the last ones, for lack of room, 

 upon the backs of the first occupants, until, on a ledge scarcely 

 twenty feet long and averaging less than two feet in width, there 

 were crowded over sixty tortoises. In a few minutes one of them 

 took alarm at something that escaped my observation and slid 

 precipitately into the water. All the others, with one exception, 

 followed the lead and in about four seconds the ledge was in pos- 

 session of one unusually large female, that, for some reason or 

 other, whether from superior experience or unusual sluggish- 

 ness, refused to leave the vantage ground.^ In a few minutes 

 the ledge was again crowded and the previous performance was 

 repeated. During the first forty-five minutes of observation the 

 ledge was vacated seven times. 



As they lay basking they were continually snapping at passing 

 insects and wriggling their feet, upon which flies and mosquitos 

 were crawling, their actions reminding one of those of a dog tor- 

 mented by flies. When undisturbed by pests, however, they 

 stretch themselves out to the fullest extent, the hind legs being 

 extended backward so that the soles of the feet are in contact. 



^. have repeatedly noticed such cases of marked individuahty among tortoises of several species 

 and am inclined to believe that one must admit that there is as marked a degree of individuality in 

 character in this order of reptiles as is acknowledged for much higher animals. 



