113 
bugs dead and covered with a fresh fungous growth left in the 
box; fresh food and about one half pint of live insects introduced. 
Box supplied with live insects and fresh food as needed. June 
30, condition of the box about the same as above. About one 
quart of chinch-bugs removed and placed in corn (B). Fresh 
food and about one pint of insects introduced. The box was left 
undisturbed, except when fresh food and live insects were put in, 
until the latter part of July. On one occasion, about the middle 
of July, Mr. Wells found a large insect, which he took to be a 
cockroach, under the box, “thickly covered with the same white fun¬ 
gus.” It was removed and placed behind a leaf sheath on corn 
(B) among “a teaspoonful of chinch-bugs,” and left several days, 
without any indication that the disease spread to the insects com¬ 
ing in contact with it. It was afterwards placed behind another 
leaf, similarly covered with chinch-bugs, where it remained; but 
at no time were there any traces of the fungus on the insects 
about it. 
August 1, the box in good condition, and several thousand fun¬ 
gus-covered bugs removed, together with nearly three fourths of 
a quart of live insects, all of which were placed in corn (B), as 
recorded under the following number. Fresh food and about one 
gill of live insects added; the box set away and not examined 
again, until September 19, at which time it was overhauled by 
Mr. Johnson. Insects all dead; the dirt in the bottom somewhat 
dry, and the food considerably molded; but the whitened bodies 
of dead chinch-bugs were very abundant. Several thousand well- 
covered specimens could have been taken out, but the supply was 
reserved for further use. 
Mr. Wells informed Mr. Marten August 8 that his contagion 
box did not work so well after he began putting in immature 
bugs; but that, altogether, he had distributed in corn about four 
quarts of chinch-bugs that had passed through his box. 
However successful this experiment may seem to have been, it 
must be borne in mind that the chinch-bugs introduced from time 
to time had been liable to infection in the fields where they were 
collected (see Nos. 55 and 57), as well as in the contagion box 
itself. 
No. 57. A farmer’s field infection experiment made by Mr. Wells 
on his farm near Farina, in corn (B). The first lot of material, 
about two thirds of a quart of chinch-bugs, dead and alive, from his 
contagion box (No. 56), was distributed June 10 behind the leaf 
sheaths and on the ground of the first, third, and fifth rows along 
the south and east sides, where the bugs covered the first five 
rows of corn. This field was examined by Mr. Marten June 19, 
but no dead bugs were seen, and only a few tracps of the original 
material were found. The chinch-bug attack was spreading rapidly, 
and corn was badly damaged throughout the south and east parts 
of the field. 
The second distribution was made June 20, the material consist¬ 
ing of about three pints of chinch-bugs, dead and alive, from No. 
—8 
