93 
other points. Frequently they partially entered the opening thus made, 
all the while sucking the body fluids, sometimes feeding until nothing 
but the shriveled grub-skin remained. Several adults issued, all prior to 
August 21, 1914, but only one was preserved. This proved to be E. 
maculatus. A larva of this species which we obtained ‘December 11, 
1915, at Louisville, Ky., in sod ground heavily infested with Phyllophaga 
and Cotinus (Allorhina) grubs, pupated July 29—August 3, 1916, and 
the adult issued September 2. Mr. George G. Ainslie collected three 
larvae of this species while following a plow at Fellsmere, Fla., March 
25, 1914, and placed them all in one box. When examined a month 
later only one remained, the others having apparently been killed and 
eaten by the survivor. This larva, which was received at the Lafayette 
Laboratory May 1, issued as an adult August 6, 1914. The larva (Fig. 
23) of this species has been previously recorded by E. S. G. Titus (73) 
as predaceous on Ligyrus grubs in Louisiana. It attacks a grub as does 
Fic. 23. Head (a) and anal seg- 
ment (b) of Hrax maculatus 
Macgq., larva. 
Promachus vertebratus, which is shown in Figure 20 in its typical posi- 
tion when attacking a grub. 
From our data the life cycle appears to be one year, the winter 
always being passed in the larval stage, pupation occurring in July and 
August, and the adult fly (Fig. 24) issuing during August and early 
September. 
The species is distributed from Pennsylvania to Central America, 
but seems to be more typically a species of the southern United States. 
According to Titus (73), the adults of E. maculatus are predaceous 
on adult tabanids the larvae of which are predaceous on white-grubs. 
ERAX AESTUANS Linn. 
This species is included as a possible enemy of white-grubs from 
the fact that it was collected in a field infested with them and does attack 
Phyllophaga grubs in confinement. A single specimen was reared by 
