Life History of Lonchaea chorea. 321 
PosITION OF THE LONCHAEIDAE. 
As regards the systematic position of the Lonchaeidae 
there would appear to be some difficulty. Originally united 
with the Sapromyzidae, they have been more recently 
separated off by Loew, Becker and other authors as a 
distinct family because of certain small differences. But 
Williston in his “ Manual of North-American Diptera ” 
(1908) includes in the Sapromyzidae the sub-families 
Sapromyzinae and Lonchaeinae. 
Economic STATUS. 
L. chorea is not known to cause much damage, although 
it may be very extensively found at times attacking crops 
of diseased beetroot. It does not frequent human habita- 
tions; so that it could not be classed with the disease- 
carrying house-fly which it resembles to a certain extent 
in its breeding habits. Rather should we class it in that 
large group in which are included all “ followers of decay,” 
in that plants, such as beetroot and certain Monocotyledons, 
which have been previously attacked by fungus or other 
destructive agencies, are hable to have the injury accen- 
tuated by the larvae of this fly. The larvae may be 
transmitted by the use of infected dung for the manuring 
of soils in which the crops liable to attack, are cultivated. 
If the dung be mixed with a small quantity of some 
chemical goil-fertiliser, such as commercial sulphate of 
ammonia, the larvae will be killed off; and at the same 
time the percentage of available nitrogen will be increased 
by the admixture of the chemical. Other dressings may 
be used with equal effect, such as the potash salts, super- 
phosphate of lime, etce.; but care must be taken to use 
them in fertilising quantities, otherwise serious damage 
might be done to the plants. The use of fertilisers as 
insecticides is by no means new, and in America at least, 
they have been long known to be effective against cut- 
worms, wireworms, scale-insects and aphides 
EXPLANATION oF Puatr XI. 
Fie. 1. Ventral aspect of larva of Lonchaea chorea: numerals 
denote number of segment. 
pt. sp. prothoracic spiracle; kw. locomotory areas ‘Kriech- 
wiilste); an. anus. 
