124 
MUSHROOMS, HOW TO GROW THEM. 
through the atmosphere, and tobacco smoke, have been 
ineffectual. Burning a lamp set in a basin of water with 
a little kerosene floating on the surface is a most doubtful 
operation. Multitudes of flies are destroyed by this lamp 
trap, but they are the poor little innocent “manure 
flies,” and the atmosphere of the house is vitiated and 
rendered: unhealthy for the crop. I have tried these 
lamp traps season after season, and never knew of their 
doing any good; that is, the maggots seemed just as 
numerous in the lamp-trapped cellar as in the other cel¬ 
lar in which no lamp trap had been used. 
Regarding this “maggots” question, Mr. J. F. Barter, 
of London, writes me: “During the summer months 
the outdoor mushrooms get maggoty before they are big 
enough to gather, but of course they can be grown in 
cool cellars all the year round. ... I know of no 
sure cure for them (the maggots); of course a slight 
sprinkling of salt with manure or mold, does prevent, to 
a certain extent, but it must be used very carefully.” 
Now my experience is, as I have already said, that it is 
impossible to grow mushrooms here in summer, even in 
cool cellars, without having them more or less maggoty. 
As regards the salt and loam preventive, I have tried it 
lightly and heavily, but without any apparent good 
effect. 
Black Spot.—All mushroom growers are familiar 
with this disease, but unless it appears in pronounced 
form very little notice is taken of it, even by market 
men, for we see spotted mushrooms continually exposed 
for sale. It appears as dark brown spots, streaks, or 
freckles, on the top of the mushroom caps, and increases 
in distinctness and breadth with age. Fig. 25. It is 
caused by eel worms (Anguillulce). These minute 
creatures enter the mushrooms when the latter are in 
their tiniest pin form and before they emerge from the 
ground. If a button arises clean it remains clean, if 
