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eggs should not be overlooked. It does not necessarily show more 
than an occasional carnivorous habit, as the attack under consideration 
occurred during extreme abundance of the locusts. The onion has 
been recorded as a food plant in England, seed potatoes have been 
attacked, according to Lintner, and hedge mustard has been recorded 
as a food plant by Slingerland. 
LIFE HISTORY. 
The life economy of the seed-corn maggot is very imperfectly under- 
stood. In spite of the many writings on this insect the species has 
evidently never been under continuous observation in any locality, and 
what has been published affords evidence only of a single generation. 
It has been surmised that the species agrees with others of its kind in 
passing the winter in the adult condition, although it is possible also 
that it hibernates, in some localities at least, as a puparium. Of one 
thing we ma}^ be tolerably certain, that only a single generation is 
developed in corn, but it is quite probable that two generations might 
be produced in beans and peas owing to the longer period in which 
these crops are kept in the field, and the second and third plantings 
that are made in many localities. In the Gulf States the flies have 
been reared as early as January 4, and the rearing notes which have 
been cited for that region show that the flies may appear through the 
first three months of the year. The fact that larvse were received from 
Texas in the middle of May would indicate a second generation in the 
South, the progeny of the flies appearing in the earlier months. Flies 
have been reared also in or from different localities in June, July, 
August, September, and December, and it seems probable that where 
weather conditions favor, several generations are normally produced 
each year, although there must be a period in midwinter in which 
breeding ceases, and possibly another in midsummer. 
Professor Forbes has admitted the probability that later generations 
might appear than that observed by him on corn, the adults from 
which emerged from June 11 to August 7. In the Northern States 
it is probable that we have at least two generations, the first injurious 
in May and June to such seedlings as are then to be found, and the 
second generation feeding upon weeds or dead or dying plants, in 
excrement and in refuse, without their presence being manifested. 
It would be interesting to learn if most of the injuries occasioned by 
the seed-corn maggot are not due to the attraction of the winged fly 
for oviposition on manure used in the field or to the decomposition of 
a portion of the seeds (something which must always happen) or to the 
presence of other decomposing material, due to natural causes, to 
fungus attack, or to infestation by primary pests. 
