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larvae and the slender dark brown chrysalides are about four millimetres in length, 

 the case six millimetres. There is only one brood in the season. The small shining, 

 Bteel-grey moths appear at the end of July and the beginniftg of August, and lay eggn 

 ■which hatch the same season and make about ^ their growth before winter sets in. 

 After feeding for a time, they fasten themselves to the bark of the tree and remain 

 dormant till spring, when they revive and attack the new foliage. 



This insect was first brought to my notice in 1889, when the late Mr. Wm. 

 Brown, of Charlottetown, P.E.I. , amongst others, sent me some larvse from his plum 

 trees, upon which they were abundant. Mr. Brown had also found them upon one 

 "Brockworth Park" pear tree and upon some apple trees. In June last, Dr. D. 

 Young, of Adolphustown, sent me specimens and wi'ote ; — 



" June 14. — I send you to-day some small caterpillars in their cases ; one end of the 

 c^se is open, and the caterpillar seems to fasten to the apple leaf and then feasts away 

 upon it. Most of the leaves of the Duchess, Golden Russet, Northern Spy, Talman 

 Sweet &c., have them upon them, and often half a dozen on a leaf They are here 

 by millions and are destroying the leaves rapidly. We have been spraying them 

 this week with Paris Green (lib. to 200 gallons), and think that a portion of them 

 are gone from the leaves of trees sprayed a couple of days ago." 



" June 24.— Having examined the worm and its work under the microscope I 

 found that it fed chiefly on the inside of the leaf; but that, to reach that part, it ate 

 a little of the epidermis first, every time it attacked a fresh part of the leaf, which 

 seems to be frequent ; we therefore from this fact determined to use Paris Green, and 

 we gave the trees a most thorough spraying. After the spraying, I thought, more 

 than before it, they seemed in almost every case to move and attack a new part of 

 the leaf, and wherever they did so they seemed to have just commenced operations 

 and died, for they scarcely made a mark on the leaf They are mostly gone, yet 

 there are thousands fast to the leaves, but they are dead. They attacked about 

 ], 000 Duchess of Oldenburgh trees, and had they continued a few days longer I believe 

 they would have destroyed the foliage and crop. They are most voracious feeders." 



Dr. Young sent me frequent consignments of these larvae, and although many 

 were dead in the cases, at the same time there were a great many that had formed 

 the chrysalis, and from most of these the moths emerged later. Dr. Young also very 

 kindly took much pains to advise me regularly how the insects were developing. He 

 writes October 3 : "I find the young worms are, as you anticipated, on the under- 

 side of the leaves. There is one or more on almost every leaf, sometimes only on 

 every 5th or 10th leaf, but pretty plentiful. They are also in the forks of the 

 branches as well as on the leaves." 



This last mentioned habit must, I think, be the usual method of passing the win- 

 ter ; none could be found on the fallen leaves 18th November. Upon several lots o^ 

 twigs sent me at different times during the winter I find the young larvae in thousands. 

 Being anxious to find out whether they might not be treated during the winter in a 

 wholesale manner, I asked Dr. Young to spray some trees with Kerosene Emulsion. 

 This he kindly did in a thorough manner, and then sent me the twigs about a fort^ 

 night afterwards. On 14th December he writes : " I now send you a package of the 

 young caterpillars. The trees off which they were taken were spi'ayed 25th Novem- 

 ber ; a light shower came that night, so I sprayed again 2nd December with Kerosene 

 Emulsion. If you still wish to have the emulsion used warm, I shall be pleased to 

 try it. In every alternate row of trees (among the Duchess) I have Golden Russets 

 of the same age (17 years). The Russets had very few apples on them, so we did 

 not spray them with Paris Green last season, and I am now satisfied that the cater- 

 pillars are many times more numerous on the Russets than on the Duchess of Olden 

 burghs. I think the Paris Green spraying last summer killed the greater proportion 

 of those on the Duchess and that the dead ones must have fallen from the leaves, for 

 they seemed so much less in numbers afterwards." 



They were again sprayed later, as here recorded : " 8th February, 1892. — I again 

 Bend you some of the case-bearers in one package containing two small boxes. The 

 flat box contains those sprayed with very warm Kerosene Emulsion. Those in the 



