82 
INSECT ENEMIES. 
The following facts concerning the life liistory of this pest had, 
amongst others, he added, been already elicited. The parent 
insect, which is a minute red-bodied gnat-like fly, whose body 
measures approximately but line in length, and which has a 
wing expansion of line, alights upon one of the florets of the 
spikelet of the broom sorghum about the time of its first opening 
and before the anthers have shed their pollen and by means of 
a needle-like retractile oi’gan — the ovipositor, which equals its 
body in length, deposits one egg or more in contact with the 
essential organs of the flower, the perfect florets being alone 
selected for this purpose. Each female insect lays from seventy 
to eighty eggs. These, which are invisible to the naked eye, are 
orange-red in colour. They are cylindrical in form, but unlike 
what has been observed in other related insects, are drawn out 
to a long blunt point at one extremity, a feature whicli doubtless 
secures them from being blown from tJieir resting place. The 
tiny maggots when hatched feed upon the ovary of the flower 
and hinder its further development, so that the formation of seed 
is altogether checked. They are about ^ line in length when 
extended, and like tlie eggs orange-red in colour. They continue 
to derive nutriment from the flower until the seed which is free 
Irom their attack is ripe and harvested, and even then many 
liave not yet passed into the pupa or chrysalis condition. These 
final translormations are undergone within the dead and often 
fungus-infested floret ; thougli the maggot has occasionally 
passed previously to the narrow space which intervenes between 
the flowering and empty glume. Home it is thought may drop 
to the ground and transloriii therein. It being impracticable to 
husk either broom sorghum seed or that of other sorghums, the 
pest may be easily conveyed from one district to another. 
Already this insect, confined as far as is at present known to 
Houthern Queensland, and believed to be a native species, is 
extensively parasitised by a minute hymenopterous fly belonging 
to the family Chalcidm, which closely resembles the parasite 
w rich Mr. Enoch has lately sent from England to the United 
States, and also to New Zealand, to assist m lessening the 
depredations of the Hessian fly in these regions. Should the 
present cecidomjid transfer its attention to the florets of other 
cereals, such as those of the wheat, or should the wheat midge 
