ANT COMMUNITIES 



insects and spiders. This ancient Florissant lake-basin 

 lies among a series of low- wooded hills and ravines. At 

 the period of the Oligocene division of the Tertiary geo- 

 logical era this elevated lake must have been a beautiful 



sheet of fresh water. It 

 was hemmed in on all 

 sides by granitic hills, 

 whose wooded slopes came 

 to the water's edge in 

 this phase not unlike 

 Lake Lonesome, among 

 the White Mountains. 

 Professor Wheeler's col- 

 lections, which I have 

 been permitted to exam- 

 ine, show the fossil ants 

 to be more abundant than 

 any other insects. But 

 only males and females 





Fig. 75 A MARRIAGE-FLIGHT, OR " SWARM," OF WINGED MALE 



AND FEMALE ANTS 



are represented, indicating that these had been sub- 

 merged in the lake during marriage-flight, precisely like 



those reported by Mr. Prime. 



176 



