2 THE POTATO-TUBER MOTH. 
potato in section; at the left is a section containing two pits, d and 
f, in which the larva has been at work, while at 6 and ¢ are shown 
the egg, highly magnified. 
DISTRIBUTION. 
This species is widespread in its distribution, but in this country, 
until the present year (1912), we did not know of its rapid dissemina- 
tion. Abroad it is well known in Hawau, all portions of Australia, 
New Zealand, Algeria, and many other countries, including southern 
Europe. As an enemy to tobacco it has been known for several 
years in Florida and in North Carolina, South Carolina, and Virginia.' 
The directions for applying remedies 
which follow are for the benefit of per- 
sons inquiring in regard to means. of 
control. Which of these should be 
used can be best determined by trial in 
the different localities under the differ- 
ent conditions in which the insect ex- 
ists. This applies especially to the 
question as to the best material for 
fumigation. 
EVIDENCE OF IMPORTANCE. 
As evidence of the importance of the 
pest a few quotations or notes should be 
made. 
Mr. J. E. Graf, working under the 
Fie. 2.—Work of the potato-tuber moth:a, direction of the writer, wrote: 
Section of tuber, showing eye and eggs 
deposited about it; b, egg in outline; c, In September, 1912, an unusual outbreak of 
egg, lateral view; d,f,mines of larvain this pest occurred at El Monte, Cal., due entirely 
potato. a, Natural size; 0, ¢, greatly en- +. 4 combination of circumstances. Thousands 
larged; d,somewhatreduced. (Redrawn 5 a E Ey 
from Riley and Howard.) of acres of potatoes were planted in southern Cali- 
fornia—many more than the market would stand. 
This meant that the market was continually clogged and the prices were poor, so that 
the crop was worked off very slowly. The tuber moth (Phthorimxa operculella) is 
alwaysfound here, but the crop is generally handled so quickly and carefully that small 
loss results. This year, however, careless work and the leaving of potatoes in the 
ground too long have given the insect a tremendous start, and now its ravages are 
greater than ever before. A combination of the moth and low prices has so discouraged 
many of the growers that they are leaving their potatoes to rot, and as these are becoming 
infested there will be a great number of moths waiting for the fall potatoes. * * * 
Later, September 17, 1912, Mr. Graf wrote in regard to this species 
that two growers near El Monte, Cal., lost $90,000 and $70,000, 
respectively, on potatoes that year. Items of this kind show the 
necessity of investigating the problem. 
11Tt is somewhat doubtful if the splitworm on tobacco and the potato-tuber moth are the same insect, 
although they appear to be identical according to the best authorities on thesubject. This is a matter to . 
be settled later. 
