REPOliT OF THE E]\TOMOLOGl)iT AyB BOTANIST 245 



SESSIONAL PAPER No. 16 



aria) appeared in vast numbers in some places on Vancouver Island this year. Strange 

 t:> say, in certain localities they were entirely absent, but in others they were so 

 numerous that they consumed every particle of their natural food, and they would 

 then attack other trees. In one > place, which I was called to inspect, I found that they 

 had attacked even the fruit on apple trees, eating away a layer of the skin and large 

 boles into the interior near the stem. They were also denuding the apple trees of 

 their leaA'CS. There were hundreds on one tree which stood beneath an oak. The larva) 

 had defoliated the oak tree, then let themselves down in the usual manner, and were 

 on the apple tree in hundi-eds eating the foliage and fruit. Other trees, as cherry, 

 elm, &c., farther away were also attacked, but not so much as those near the oaks.' 



This variation in the food habits of this insect can, I think, only be considered 

 as exceptional. The natural food of the species in Vancouver Island is the pictur- 

 esque oak, Quercus jacohij K. Br., which grows round the southern end of Vancouver 

 Island. Among the caterpillars forwarded by Mr. Anderson, some parasitized speci- 

 mens were found, from which was raised a parasite which has been kindly identified 

 by Mr. W. H. Harrington, as Pimpla Ontario, Cress. Another parasite, the species 

 usually responsible for the svidden reduction in the numbers of this species, is Ichneu- 

 mon cestus, Cr., a yellowish brown ichneumon fly about three-eighths of an inch long, 

 with one black band across the abdomen, and was found in considerable numbers by 

 Mr- A. W. Hanham, who writes: — 



' Victoria, B.C., October 25. — The moths of the Oak Looper {E. somniaria) have 

 this autiunn been a sight to see. Out the Cadboro Bay road large oak trees were 

 covered with the moths a couple of weelis ago, particularly on the underside of the 

 branches and close to the trunks. There were numbers of a reddish brown ichneumon, 

 all of one species, which were flying about the trunks of the trees. I bottled several 

 of these, which I send you.' 



The specimens forwarded by Mr. Hanham were Ichneumon cestus, Cr. 



The White-marked Tussock Moth [Ilemerocampa (Orgyia) leucostigma, S. & A.] 

 — This common pest of cil/ shade trees, which was referred to at some length in my 

 last report, continues to injure shade trees in some of our cities. The most effective 

 remedies are the collection of the egg masses in winter and the spraying of the trees 

 with arsenical poisons in spring before the caterpillars (Plate II., fig. 9) have grown 

 much and injiu'ed the leaves. The Toronto civic authorities are this year taking 

 active measures to clear out the infestation, which for many years has injured the 

 appearance of the beautiful horse chestnut trees for which Toronto is celebrated. A 

 reasonably large sum of money has been voted for the collection and destruction of 

 the eggs during the present winter; and there is every reason to hope that by this 

 means private individuals may be stirred up to do their duty in the public interest 

 by destroying the eggs on their own trees in winter and then spraying the foliage in 

 summer for a year or two. 



Walking Stick Insect (Diapheromera femorata, Say). — A remarkable outbreak 

 of the Walking Stick Insect, which is worthy of record, is reported by Mr. J. E, 

 Williams, of Toronto. This is usually a rather uncommon insect; but Mr. Williams 

 found it in such numbers in the Niagara Glen that thousands might have been col- 

 lected on oak and butternut trees during September. These trees are ordinary food 

 plants for this curious insect, which belongs to the Phasmidic, a division of the 

 Orthoptera, the same order as contains the locusts and grasshoppers. 



