124 
brown thrush, and the crow blackbird devour much the largest 
numbers of these insects," although it is possible that if the 
smaller insectivorous hawks—the sparrow hawk especially—were 
permitted to increase freely they would equal or surpass* * * § any of 
these, because of the greater number of insects which they take 
at, a meal. Chickens, ducks, and turkeys are fond of white 
grubs, and may often be seen scattered over fres_hl.y plowed 
ground in search of them and other subterranean insects. 
Mammals .—The only native mammals known to feed on these 
insects in any considerable numbers are moles, ground squirrels, 
and skupks—none of them very likely to be tolerated by the 
farmer, whatever may be their insectivorous habits.t 
Among the domestic animals, pigs are well known as eager 
hunters for white grubs, in search of which they diligently root 
up an infested turf; a fact which may sometimes be advantage¬ 
ously applied for the protection of corn to follow upon grass. 
Insects .—The special insect enemies of the white grubs now on 
record belong to three or, possibly, four species, two of them 
hymenopterous and one dipterous, a second dipterous insect 
bred by us from dead white grubs being doubtfully parasitic. To 
this number I am able to add another hymenopterous parasite, 
Pelecinus polyturator, a remarkable insect whose larval his¬ 
tory has heretofore been wholly unknown. From a collec¬ 
tion of white grubs obtained from an orchard at Champaign, 
Illinois, May 9, 1892, and kept in a breeding cage at my 
office insectary, a specimen of Pelecinus polyturator emerged 
August 26, 1892. As the parasite was seen in the act of emerg¬ 
ing from its pupal envelope, there can be no doubt of either the 
fact or the date.! An examination of the remains of the grub 
containing the pupa skin of the parasite showed that the former 
belonged to the species L. gibbosa. My office specimens of the 
adult of this parasite are recorded under nine collection num¬ 
bers, all bearing dates in late summer and early fall—July 21, 
26, August 1, 2, 11, 16, 28, and September l and 16. It is 
hence probably single brooded, maturing in July and August. 
Perhaps the most destructive insect enemy of the \Vhite grub 
is Tiphia inornata , Say, a hymenopterous species which we have 
never bred, but which has been reported by Dr. Riley § to occur 
occasionally in very large numbers in ground infested by Lach- 
nosterna larvae. He says: “One can scarcely dig for half an 
hour in any soil in this part of the country, without meeting 
with a curious egg-shaped cocoon, of a pale golden brown or 
* Nine out of forty-four robins shot by me in April, May, and June had eaten June 
beetles; six catbirds out of forty-one; and twelve brown thrushes out of forty-three. 
t Raccoons and bears, both of which are sa'id to be fond of these insects ("Insect Life,” 
Voi. II., p. 373) are still less likely to be permitted to indulge their liking. Badgers and 
weasels are said by liiley to devour the grub (Sixth Mo. Rep). 
+ The adult Pelecinus, its pupa skin, and the remains of the parasitized grub are all in 
my laboratory collection. (Nos. 18843, 18844, and 18845). 
§ Sixth Ann. Rep. State Ent. Mo., p. 122. 
