2 INSECTS INJURIOUS TO MUSHROOMS. 
They are the young of certain small flies or “ gnats,” two-winged 
and mostly black in color, of several species belonging to the fami- 
lies Mycetophilide and Phoride, and to the genera Sciara and 
Aphiocheta. Of these the species belonging to the genus Sciara are 
by far the most common and injurious of mushroom pests. They are 
minute in size, measuring about three thirty-seconds of an inch in 
length and about one-eighth inch in spread of wings. They are 
smoky or dusty black in color. The species attracting most atten- 
tion as pests are Sciara multiseta Felt and Sciara agraria Felt. Both 
species are, like the other mushroom gnats, rapid and prolific breed- 
ers, especially during warm weather, frequently occurring in mush- 
room houses so abundantly as to darken the windows. They may 
be readily confused, however, with gnats of the same genus which 
‘breed in manure or in greenhouse soil, and determinations should 
always be made by a specialist. 
Another common species, Aphiocheta albidihalteris Felt (fig. 1), 
superficially resembles the preceding, and has much the same habits, 
but as yet has not appeared to cause so much damage as have the 
species before mentioned. 
The life history of one of the een oon maggots is about as fol- 
lows: The eggs, of which each female is capable of laying nearly 
1,000, are generally deposited at the juncture of the stem and cap of 
the mushroom, or in the manure or soil at its base. In a warm tem- 
perature they may hatch within three days, but in colder weather this 
time may be considerably extended. Upon hatching the larve bore 
at once into the stem or cap of the mushroom, soon riddling the cap, 
and causing the breaking down of the mushroom in a short time. 
On account of the perishable nature of their host they pass through 
their transformations quickly, the larve feeding for from 7 to 10 
days, by which time the entire cap is destroyed. The larve then 
enter the ground, each spinning a slight silken cocoon just beneath 
the surface, and pupating. The pupa stage lasts from four to 
seven days, after which the insects emerge as adults, soon afterwards 
pairing and ovipositing for the next generation. Owing to the 
immense number of eggs deposited and to the short life-cycle the 
rapidity of their increase is remarkable, so that the presence of only 
a few insects in the mushroom house at the beginning of the season 
may result in the presence of millions after the beginning of warm 
weather, thus effectually preventing the cultivation of mushrooms. 
CONTROL. 
It is evident that in the control of the mushroom maggots measures 
should be undertaken early in the season for their elimination from 
the mushroom house and precautions observed against their subse- 
