578 VICTOR E. SHELFORD 
The Cumberland mountain district was originally completely 
forested. The forest of the valleys was chiefly beech and maple; 
of the mountain slopes, oak and hickory; of the mountain tops 
con.fer. The soils are various, resulting from many different 
kinds of rock. We were unable to find this species in the strictly 
red cedar, pine or beech forest. However it occurs in the more 
mesophytic oak containing ravines of strictly conifer forests and 
in forest of mixed oak and conifer. Sherman records it from such 
situations also. This is not true near Chicago. 
The beetles come out into the little streaks of sunshine on fallen 
trees and bare ground in the early forenoon to feed. The writer 
has seen them picking up insects from the logs in such locations. 
From my observations in the field I am confident that bare spots 
of mineral soil, fallen trees, etc., are essential to this species. 
Fig. 17 The burrow of sexguttata. One-third natural size. 
It is only in such places in virgin or little disturbed forests that 
I have found them copulating. However it is not a particular 
type of forest that is essential to this or any other species of tiger 
beetle, but a certain environmental complex in which a certain 
‘consistency and moisture of soil and a certain amount of sunlight 
and bare ground are the essential things. 
3. Ecological relations of larvae. a. General behavior. The 
burrow resembles that of C. limbalis and is shown in fig. 17. 
This larva is less active than those of the other species, but other- 
wise is similar in habits. 
b. Local distribution. The larvae of this species are very 
difficult to find because they are for the most part under leaves. 
