THE CLover SEED CHALCID 109 
Efficiency of the Parasites. The following figures are taken from 
our notes. A lot of alfalfa pods collected when ripe gave in the insec- 
tary 151 adults of B. funebris and 165 of H. medicaginis which means 
that over 52 per cent of the Bruchophagus larvae were destroyed. I. 
longfellowi did not appear in this 
lot, altho we have found it in alfalfa 
at other times but never so numer- 
ous as the other species. In a lot 
of red clover seeds, which gave in 
the breeding cage 1,216 adults of 
B. funebris and 176 parasites, the 
latter comprised 156 of J. longfel- 
lowi and 20 H. medicaginis. In an- 
other lot of red clover seeds there 
emerged 937 B. funebris, 86 I. long- 
Fig. 25. a. ees of male I. longfellowi. fellow and I4 HT. medicaginis. 
b. Pupa of female I. longfellowi. From a lot of alfalfa pods we 
reared 151 adults of B. funebris and 165 adults of Habrocytus medt- 
caginis. If we assume that each parasite emerging represents one 
Bruchophagus larva destroyed, then the original number of Brucho- 
phagus larvae was 316, of which over 52 per cent had been killed by 
the parasite. 
SUMMARY 
The clover seed chalcid, at first thought to be parasitic on weevils 
infesting seeds, is now recognized as one of the worst pests of clover 
and alfalfa seed. 
The adult is a small, black, wasp-like four-winged fly easily mis- 
taken for a gnat by one not familiar with it. The egg, which is in- 
visible to the naked eye, is deposited in the soft green seed of clover 
or alfalfa. The larva hatching from it is white and maggot-like, fill- 
ing the empty shell of the seed when it is full grown. The pupal stage 
is of short duration. The adult in emerging gnaws a hole through the 
seed shell and escapes. At least two generations appear during the year. 
The species hibernates in the larval stage inside the seed. 
The clover seed chalcid is found throughout most of the United 
States. In Minnesota, it appears to be present wherever clover is grown. 
It is found also in Germany, Turkestan, Chile, Turkey and Siberia. 
The first adults appear in June. They are most abundant about 
the middle of August and are numerous again in the early part of 
September. A few may be found until October. 
