THE POTATO TUBER MOTH. 6 
POSSIBLE ORIGIN. 
A study of the literature shows that the tuber moth was known to 
be present almost simultaneously in Australasia, the United States, 
and Algeria. It is indeed strange that, considering this fact and, in 
addition, the fact that this country is the home of a wild potato 
and tobacco, of all the entomologists who have studied the tuber 
moth, only one, Gerald McCarthy (31), who found the tuber moth 
mining tobacco in North Carolina in 1897, should claim that this coun- 
try is its native home. McCarthy also found the moth in Solanum 
carolinense, a native weed common in the southeastern part of the 
United States. Speaking of the tuber moth, he says, "This insect 
probably inhabited its present range prior to the coming of the white 
man." 
Dr. Picard (83, 84), a prominent authority on this insect, says that 
a Mediterranean origin for this species must be excluded. Consid- 
ering the fact that he has not found a specific natural enemy, in the 
shape of a parasite, on the insect, his opinion must be given consider- 
able weight. He mentions either Australia or the United States as a 
possible origin for the tuber moth. 
Analyzing the facts as presented by these two countries, it is seen 
that it was reported from both places at practically the same time. 
Edw. Meyrick, one of the earlier authorities on the Microlepidoptera, 
states that it is not an Australian form. In addition, there is no 
mention of any natural enemies of the species, which is quite signifi- 
cant, considering that many competent entomologists have worked 
on it in Australia. 
On the other hand, in the United States there are several parasites 
on the tuber moth, and, as previously stated, this country is the home 
of a wild potato and tobacco, its two favorite food plants. When it 
is considered that it was not until the sixteenth century that the 
potato was introduced into Europe, and that it was not until many 
years later that the use of the potato became at all general, it seems 
only reasonable to suppose that the rapid dissemination of the tuber 
moth came about by following the potato " around the world. " 
Furthermore, the tuber moth is an insect which could be introduced 
easily from one locality to another, as once it infests potatoes it is 
assured of food enough to carry it through several generations; and 
as the insect can stand lower temperatures than the tubers, it would 
never be in danger of being killed by freezing. 
The entire economic history of the tuber moth is another indication 
that it originated in America. Losses reported to potato crops in Al- 
geria, India, Tasmania, South Africa, Australia, and New Zealand 
are far heavier than any ever reported from California or Texas. 
Climatic conditions being equal, it is generally true that a pest is more 
injurious in an adopted home, for a time at least, than in its natural 
