92 
soft-bodied insects and possibly also on earthworms. We have no 
record of the number of grubs which a single vertebratus larva may 
destroy but it is doubtless several, possibly many, and it undoubtedly 
ranks as one of the most important natural enemies of the common 
white-grub. 
PROMACHUS FITCHII O. S. 
According to Aldrich’s catalogue (1) this species has been recorded 
as occurring in Missouri, Kansas, Nebraska, Florida, and Connecticut, 
and we have reared it from larvae collected in the grub-infested areas 
near Richland, Mich., and Madison, Wis. The larva of P. fitchii was 
first reported as predaceous on grubs by Dr. E. P. Felt (18) who found 
it very abundant in fields heavily infested with white-grubs in New 
York, in some cases outnumbering the grubs. According to Dr. Felt’s 
observations the larvae live in the ground at least two years, and it is 
believed that they have a three-year life cycle—which would correspond 
exactly with the length of the life cycle of the more injurious species of 
Phyllophaga in New York—a very important factor where only one 
destructive brood occurs every three years. There is little doubt from 
Dr. Felt’s notes that this larva is as destructive to grubs in New York 
as is P. vertebratus in the central states. 
According to our rearing records pupation occurs usually in June, 
although occasionally in May, and in every case the pupal period was 
almost exactly 30 days in length. 
We are unable to distinguish the larvae of fitchii from those of 
vertebratus although the mature larvae of the latter are much the larger. 
The pupae are likewise very similar, but are separable according to Mr. 
J. R. Malloch (48). The adult of fitchii (Pl. VII, Fig. 27) is smaller 
than that of vertebratus and quite unlike it in appearance, the body of 
the former being covered, sparsely in parts, with golden hair. 
PROMACHUS BASTARDIT Macq. 
This species, which has not been seen by us, occurs in the Eastern 
States, and Mr. H. E. Smith states that the larvae are predaceous on 
Phyllophaga grubs in confinement cages. From this observation and 
from the known habits of the closely related species already mentioned, 
there is little doubt that P. bastardu attacks grubs under normal field. 
conditions. 
s Erax MACuLATUS Macq. 
(Syn. E. interruptus Macq., and E. lateralis Macq.) 
Of the several species of Erax known to attack white-grubs, macu- 
latus is the most common and beneficial. While following the plow 
near Greenwood, Miss., in March and April, 1914, Mr. H. E. Smith 
found many asilid larvae, the fields being in all cases infested with 
white-grubs to a greater or less degree; and in one or two instances the 
larvae were seen feeding on grubs. In confinement the larvae, which 
were believed to be of a single species, readily attacked grubs, usually 
puncturing the host on the dorsum near the head, but sometimes at 
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