THE MASTERY OF THE AIR 265 



I saw one of these animals run up a trunk in 

 a rather open place, and then glide obliquely 

 through the air to another tree on which it 

 alighted near its base, and immediately began 

 to ascend. I paced the distance from one tree 

 to the other, and found it to be not less than 

 seventy yards, and the amount of descent I 

 estimated at not more than thirty or forty feet, 

 or one in five. This, I think, proves that the 

 Colugo must have some power of guiding itself 

 through the air, for otherwise in so long a 

 distance it would have little chance of alighting 

 exactly on the trunk." 



An interesting point in regard to these 

 parachuting mammals is that there are so 

 many which seem to be independent of one 

 another. It is worth while making a technical 

 list, because it shows how the same impulse 

 must have become urgent over and over again. 



f Perhaps to be ranked 

 GALEOPITHECUS . . . A 



I among the Insectivores. 



Among the rodents, re- 

 ANOMALURUS .... 



lated to squirrels, but 

 PETAURISTA 



differing markedly from 

 SCIUROPTERUS .... 



I one another. 



PETAURUS TA11 of them Marsupials, 



PETAUROIDES . . . J but not nearly related 

 AEROBATES I to one another. 



