98 Introduction to Insects [cH. 
insects directly, usually by stopping the breathing 
pores. A mixture consisting of soft soap and sub- 
stances such as tobacco infusion or paraffin is often 
used in such cases. 
CHAPTER IX 
BUTTERFLIES AND MOTHS 
Surface Caterpillars. 
There are a number of moths whose caterpillars 
damage many crops by feeding on them below the 
surface of the soil or at the soil level. This habit 
gives them the name of Surface Caterpillars. There 
are several different kinds, but the damage done by 
them is very similar and the means of keeping them 
under control are the same, so for our purpose we may 
group them together. 
The chief offenders are: 
Agrotis segetum ... .... The turnip or dart moth. 
Agrotis exclamationis ... The heart and dart moth. 
Triphena pronuba _..._ The yellow underwing moth. 
These do considerable damage to mangolds, turnips, 
carrots, parsnips, cabbages, potatoes, wheat and grasses. 
They attack most cultivated plants, but are partial 
to certain species. 
They live as caterpillars during the greater part of 
the year. In the early summer they destroy young 
mangolds and turnips by cutting through the roots just 
below the surface of the soil before and after they have 
