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season. From all of the information we have at present obtained it 
would seem as though outbreaks of this pest may be largely prevented 
in this way, and it has been demonstrated by actual experimentation 
that the insect can be destroyed by spraying the plants along the 
edges of the fields when they first begin to show the effects of attack 
with a mixture of 1 pound of whale-oil soap dissolved in 8 gallons of 
water. 
Although this thrips in Russia is a tobacco insect, it invariably 
declined to feed upon tobacco with us, and held strictly to the onion. 
Lest I might be mistaken in regard to the species, specimens were sub- 
mitted to Mr. Pergande, who compared them with Russian specimens, 
and informed me that there was no doubt but that we were dealing 
with the true Thrips tabaci. 
In early April, 1897, the writer found adults of W/yochrous denticollis 
attacking young corn in the fields in Tensas Parish, La. No serious 
injury, however, seemed to follow, and this, so far as known to me, is 
the only published record of the food habits of the insect. On June 
2 Mr. Alva Agee, of Cheshire, Gallia County, reported that the insect 
had attacked the young corn in his neighborhood, apparently working 
serious injury. Specimens of the beetles were sent with the complaint. 
On June 4 my assistant, Mr. Newell, was sent to the locality to inves- 
tigate the outbreak, and found that the territory infested comprised all 
the cornfields contained in an area of 3 miles square. In all cases the 
infested cornfields were upon land which had been the year previous 
either in pasture or lying out wild. A very few of the beetles were 
found upon blue grass. In the insectary, however, they seemed to 
prefer corn first, next timothy, and lastly the blue grass. In this case 
the beetles were not observed to feed upon the stems of the corn plant 
below the surface of the ground, but upon the leaves and leaf sheaths. 
The feeding was done during the morning and evening, or upon cloudy 
days. When there were drifting clouds the beetles would come out 
and feed while the sun was under a cloud, but go back into their hiding 
places in the ground when the sun came out bright and warm. Dur- 
ing the day they were observed to hide in the crevices of the soil and 
in the loose dirt near the corn plants, from 2 to 15 being found in close 
proximity to the different hills. The beetles are densely punctate on 
the back, and these cavities retain more or less of the soil, which gives 
the beetles the same general color as the ground. They seem to have 
no inclination whatever to fly, but run quite rapidly. One female that 
was dissected contained 5 yellow, cylindrical eggs, estimated to be 
about 1 mm. in length. 
It would therefore appear that the insect is one that feeds upon, and 
probably its larve also develops upon grass. In the latter stage it 
appears to be of subterranean habits. At present no remedial or pre- 
yentive measures have been tried. 
