97 
Chinch-bugs in Boxes .—In our experiments with the transfer of 
muscardine to healthy chinch-bugs by enclosing them with speci¬ 
mens dead with disease in especially prepared boxes, we found 
that a layer of moist earth in the bottom of the box was an im¬ 
portant aid to success, and that garden soil was better than sand. 
We had also abundant evidence that these experiments were most 
successful with weakened insects, and especially with those brought 
in from the field after the older generation present had passed its 
reproductive period and was consequently about to die. On the 
other hand, adults in coiiu were occasionally found, one or both 
of which had died of muscardine. 
Owing to unskilled methods of preparation and packing, and 
likewise to delays in transit, a large part of the material sent to 
the office was either dead when received or in a badly damaged 
condition. Although the worst of this material was always re¬ 
jected, dead bugs accumulated so rapidly in our contagion boxes 
as to foul the contents, and to breed numerous blow-fly larvae 
and masses of Anguillulidae, and thus practically to interrupt the 
growth of the Sporotrichum. To avoid these disadvantages large 
reception boxes were prepared, each provided with a second bot¬ 
tom of coarse slats, a few inches above the first. The chinch- 
bugs received were placed on the lower bottom, and the vegetation 
used for food was laid upon the slats. When additions were to 
be made to the contagion boxes the stalks of corn and other food 
were taken out and beaten and shaken over the boxes, only the 
stronger and better-fed insects being thus transferred. The sup¬ 
posed weakening effect of close confinement in a saturated atmos¬ 
phere was also avoided in this reception box by leaving it open, 
the escape of the bugs being prevented by heavily chalking the 
inside of each box for four or five inches downward from the top. 
This chalk-band was renewed occasionally, as it was worn away 
by the chinch-bugs in their efforts to escape. The same device 
was used to confine the bugs in the contagion boxes when these 
were opened. While this procedure had the effect to eliminate 
the difficulties due to dead and rotting insects, it also brought 
the development of the fungus practically to a stand, and it was not 
until these more hardy chinch-bugs had been kept in confinement 
for some weeks that they began to suffer noticeably from mus¬ 
cardine. 
The difficulties due to the appearance of mites in the infection 
box have already been referred to. Minute Anguillulidae, so 
abundant among dead chinch-bugs as to form gray patches here 
and there, did not seem to affect the growth of the fungus, neither were 
the blow-fly maggots especially injurious to these cultures so far 
as we could observe. On the other hand, as both these forms 
devoured dead chinch-bugs indiscriminately, they doubtless inter¬ 
fered with the development of the fungus in the boxes. 
—7 
