CLOVER STEM-BORER AS AN ALFALFA PEST. 19 
NATURAL ENEMIES. 
TOADS. 
_ The clover stem-borer, like many of our older native species, is in 
a ereat majority of cases kept in check by its natural enemies. During 
the past few years practically every toad that has been killed by 
any of the men carrying on this investigation has had several adults 
of this beetle within its stomach. Tyler (11) has reported this 
species as being present in the stomachs of toads. Doubtless these 
batrachians eat a great many Langurie during the course of a year, 
and because of the fact that toads are largely insect feeders, they 
are deserving of careful protection from farmers. 
BIRDS. 
The Bureau of Biological Survey has found specimens of Languria 
mozardi in the stomachs of the following species of birds: Traill fly- 
eatcher (Empidonaz trailli), starling (Sturnus vulgaris), meadowlark 
(Sturnella magna), mockingbird (Mimus polyglottos), Carolina wren 
(Thryothorus ludovicianus), and robin (Planesticus migratorius). 
PARASITES. 
The most important natural enemies, however, that aid in con- 
trolling this species are its hymenopterous parasites. : 
In his early observations upon this species, Prof. Comstock (8, p. 
199) noted that: 
Two parasites were found within the burrows of the stalk borers, the one a small 
black chalcid, the dark, naked pupa of which was often met with, and the other a 
yellowish ichneumonid, the pupa of which was inclosed in a delicate white silken 
~ cocoon. 
In 1890 Weed (13) also reported a black chalcid as an external 
pupal parasite. This was doubtless the same species as that re- 
ported by Comstock a good many years previously. Folsom (16), 
in 1909, again noted the black chalcid in considerable numbers, 
this being evidently the same one referred to by Weed and Com- 
stock. Folsom also took an ichneumonid cocoon from a Languria 
burrow which disclosed an adult after a pupal period of 4 days. 
Among the Bureau records we find one by C. V. Riley, who reared 
a scelinid larval parasite. 
HABROCYTUS LANGURIA. 
The authors of the present paper have noted three rather im- 
portant parasites of this species. Habrocytus langurie Ashm. (fig. 6) 
is without doubt of the greatest importance. Often as high as 30 
per cent of the larve of Languria are parasitized by this species. 
The Habrocytus adult oviposits through the wall of the alfalfa 
stem into the tunnel occupied by the Languria larva, and within 
