158 ENTOMOLOGICAL NEWS [April, '12 



Having- exhausted that colony, I passed on to another large 

 rock, raised it, and again I could see signs of burrows and 

 one or two senilis were in sight. So I determined upon a more 

 systematic study of the burrows. The diagram shows the re- 

 sults. 



There was one main gallery (D) with branches leading dis- 

 tinctly to the margins of the rock impression (A), and each 

 branch was closed with dirt as before ; some of the branches 

 ended blindly (E). 



In one end of the gallery I found five individuals that exhib- 

 ited scarcely any signs of life ; in the blind branches of the 

 gallery there were usually one or two specimens. The main 

 gallery was not more than one-half to one inch below the sur- 

 face of the dirt (broken lines), and came to the surface 

 wherever the continuous line (F) is shown in the diagram. 



A number of individuals were enclosed in oval cells (G), 

 resembling a pupal cell ; these were apparently cut off from 

 any exit, or at least I could not trace it to the margin of the 

 rock impression. But as a rule a pile of dirt was opposite to 

 these isolated cells, as in cases where the connection was evi- 

 dent. 



I consider that the gallery was not community property 

 through instinct, but through accident, as each Cicindela in 

 nearly all instances had its corresponding pile of dirt at the 

 margin of the rock impression. In most cases it was clearly 

 to be seen that a burrow had been dug from periphery to 

 center, and that the dirt had been pushed outward interruptedly 

 as indicated by the transverse markings of the filled burrows. 



The different individuals of the colony, in working centrally 

 beneath the rock, would eventually meet each other, their bur- 

 rows uniting; this being the case, it would undoubtedly modify 

 and convert the gallery into community property, with the re- 

 sult that there would be an amicable association of individuals, 

 which at other times would be decidedly bellicose. 



Such an association apparently aroused a latent social in- 

 stinct that is so well exhibited by many other species, especially 

 the Coccinelidae, and for that matter some species of Cicin- 

 delae are social, but not all. 



