APPENDIX. xxxv 



If 80,000, as reported, were collected last year, perhaps from 

 15,000 to 20,000 might be secured this year. Arranged in a 

 single layer, a case not exceeding twenty-five square feet of area 

 would be ample for them, and leave space at one end for feeding 

 larvae. 



By means of cold storage, delay the development and emergence 

 of the parasites until larvae are in readiness in which they may 

 oviposit. 



Egg-clusters collected this season shall be so regulated by 

 temperature that they will give out their larvae as soon as food is 

 obtainable for them. 



With the feeding larvae in one part of the case with the pupae, they 

 will at once be found by the parasites and all of their eggs deposited 

 in them if the larval supply is proportioned to their need. 



When the parasitism is finished, the larvae may be fed in con- 

 finement to maturity, if practicable, provided that conditions 

 favorable to the prevention of disease or other fatality can be 

 given them ; or they may be transferred to isolated trees selected 

 for the purpose, where they may complete their growth and be pro- 

 tected from destruction by birds by inclosing the trees in netting. 

 The following season the parasites, unless desired to extend their 

 multiplication by again rearing them in confinement, may be per- 

 mitted to escape and seek their prey abroad. 



The parasitized caterpillars might be conveyed to the localities 

 where the parasites are the most needed. 



Gathering the parasites from the case after their death would 

 give every species which was parasitic on the larvae and pupae 

 (except such as may have emerged from the larvae), and their 

 proportionate number, from which the most efficient could be 

 ascertained. Examination would also show the proportionate 

 number of pupae that had been destroyed by parasites. 



The above plan may not have been properly digested by me, 

 and there are no experiments of the kind to serve as a guide. So 

 far as I know it has not been attempted on a large scale (the 

 multiplication of icerya parasites in California was somewhat 

 similar) , but if done with the knowledge that you could bring to 

 bear upon it, I am sanguine of its success. Possibly by this 

 means only can the desired extermination of the gypsy moth be 

 attained. 



If, under the existing law, the carrying of the living insect 

 from one town to another is prohibited, amendment for the above- 

 named purpose could no doubt be secured. 



Very truly yours, 



J. A. LlNTNEB. 



