190 EXPERIMENTAL FARMS. 



pods, were often eaten, however. The caterpillar has so far appeared to give its atten- 

 tion solely to partially matured pods, never to very immature pods, and (so far as I have 

 noticed) not as yet to pods nearly or wholly dried and mature. What does this mean 1 

 I find the caterpillar (both very small and apparently nearly ready to change into a 

 chrysalis) in almost fully developed pods, never in very ripe or very green flat ones. The 

 assumption is that the caterpillar only works with partially matured pease. How is it 

 then that I have never found as yet this season fully matured pods at all damaged, 

 although I have opened several ? I confess that this fact rather puzzles me. 



" Now, as to the date when the caterpillar finishes its work, I send you to-day 

 unopened a pod with a hole in it, the first which I have seen. You will probably see, 

 when you open it, that it contains some damaged pease only and not the cause of the 

 trouble. In the same box you will notice a caterpillar which appeared to me to be ready to 

 pupate, and the pod in which it was contained. Judging from the perforated pod and 

 the mature look of some of the caterpillars, I imagine that the larvae are only now reach- 

 ing full growth. Some, however, which I saw yesterday are very young, not many days 

 old. Either the season for oviposition is very extended, or we have two species or two 

 forms of the same moth to deal with. 



" With the exception of the crop which I examined to-day, all the early varieties 

 have been harvested. Some will be threshed very soon, others not perhaps for some 

 weeks. I will try to find the chrysalis. I think that it will be found under straw in 

 barns or somewhere thereabout. 



" You say that only in late years the damage has been so great as to attract atten- 

 tion. Farmers and dealers here say the damage of late years has not been greater than 

 before. That they have always noticed the injury and sometimes as causing more loss 

 than now." 



" July 30. — I now want to find out where the pupae are to be found. So far I have 

 not found any quite mature pods with either damaged pease or caterpillars in them, pro- 

 bably because they matured too early to be affected, and not that the caterpillar cannot 

 eat the hard, mature pease. In a bin of Black eyes of last year's growth I find that by 

 far the larger number of damaged pease are quite mature, proving, I think, that the 

 larva continues to feed on them until full grown, whether the pease are hard or not." 



" August 3. — I examined a crop of dwarf pease last Wednesday, and found that 

 a portion grown on low land, badly stunted by wet, was very much injured by the ca- 

 terpillar, while the higher portions of the field escaped serious damage from it. During 

 the winter, when the farmers bring in their pease, I hope to get some evidence as to 

 the influence of sowing early or late, on high or low land, &c. In a crop of dwarf pease 

 which I examined on the 1st of August, nearly all the grubs had finished their work and 

 left the pods." 



" October 22. — In accordance with your request of some months ago, I send you 

 to-day some perforated pea pods. Also in a pill box the only cocoon which I have 

 found naturally placed. It was found in a pea field, loosely attached to the under sur- 

 face of a stone. 



" Early pease this year escaped with very little injury from the caterpillar. The 

 later common pease are damaged to about the same extent as in the average of former 

 years. The damage this year is certainly less than in some seasons past, but greater 

 than in others." 



" December 22. — The farmers here are almost all of the opinion that early sown 

 pease escape the caterpillar better than those sown later. One or two say that very 

 late sowing is of benefit ; but this is opposed by the general opinion. Early peas are 

 - always damaged less than late pease, although I hear that early ripening varieties are 

 sometimes badly damaged. They have, however, I believe, a much better chance than 

 later ripening varieties. High ground is supposed to produce crops more free from 

 ' worm ' eaten pease than low land. Some farmers think that pease are more liable to 

 damage in dry seasons than in wet ones. Regarding the time during which the dam- 

 age is done, I do not know when it begins, but I think it only ends when the pease get 

 too hard to gnaw. I noticed several caterpillars (one only half grown) on August 23 

 in a small lot of late garden pease. I opened a cocoon a few days ago, and found the 



