I20 AGRICUI.TLRE OF MAINE. 



to reach our present list of two or three that are really effective. 

 In this work our government has received much aid from the 

 entomologists of ]uiroj)e and Japan, although in the final de- 

 cision we have been obliged to rely on our own judgment. Many 

 parasites that are effective in Japan are found to be worthless 

 when transplanted to another climate and bred under different 

 conditions. All of this knowledge has been worked out with 

 infinite patience and care until the problem has well nigh been 

 solved. The best results can only be accomplished when we have 

 a series of parasites that will attack the moths at different peri- 

 ods of their life cycle. For example, one parasite should attack 

 the egg cluster w4iile another one should be bred for the pupa. 

 This is known as the sequence theory, and on this problem the 

 government experts are now working. The beetle cannot be 

 depended upon to destroy the Ggg cluster of the gypsy moth, 

 how^ever destructive it may be to the caterpillar, but with a chain 

 of parasites the work of extermination would be thorough and 

 complete. While the Japanese parasites are by far the strong- 

 est and best that have yet been developed, what we really need 

 is one that is exclusively American in its character and habits. 

 This problem is being worked out and our own state laboratory 

 is doing its full share in this labor. In Japan this has already 

 been done and in that country they have a different parasite for 

 every stage of the brow^n-tail and gypsy, from the egg clusters 

 to the developed caterpillar. 



There are two parasites for the brow^n-tail and these are 

 known as the Apanteles lacteicolor and the Meteorus versicolor. 

 The first named of these is the most destructive. Still another 

 parasite destroys both the g}'psy and brown-tail and the tech- 

 nical name of this one is the Compsilura concinnata. The life 

 cycle of all three of these parasites is practically the same. 



The Apanteles lacteicolor are first obtained from the govern- 

 ment laboratory at Melrose Highlands and come as pupae. 

 About five hundred of these are placed in a perforated tin box 

 and this box is fastened to a tree infested with brown-tails. 

 Tar or tanglefoot is placed about the box to prevent ants and 

 other insects from entering the little holes in the box and destroy- 

 ing the pupae. In seven days the pupae hatch and then emerge 

 as small flies. Then begins the hunt for the brown-tail cater- 

 pillar and each female parasite deposits about one hundred and 



