88 THE EEPOET OF THE Xb. 36 



It appears, then, to be possible that we may yet control such species as the 

 Larch Saw-fly in limited areas of our forests, in touch with civilization, by an 

 elaborate system of information and distribution of parasites. 



Investigations in England by Dr. Hewitt, and others, have given hope that 

 Mesoleius may be much more effective in its control than any native species. The 

 introduction of this species may be of great benefit. ^ 



Lophyrus ahietis has been quite destructive to spruce shade trees in various 

 localities. I noticed several white spruces in Algonquin Park, Ontario, this sum- 

 mer, completely defoliated by it. 



Chermes similis, Gillette, and Chermes ahietis^ Choi., have both been destruc- 

 tive to shade trees and are very common locally in spruce forests. They may be 

 controlled on shade trees by spraying with kerosene emulsion or whale-oil soap ; or, 

 on small trees, by picking and burning the galls. 



Chermes pinicorticis. Fitch., is a common and destructive species throughout 

 eastern Canada, and seriously injures many young white pines, particularly those 

 growing in the shade. 



Chermes strohilohius, Kalt., and Goleophora laricella were particularly abund- 

 ant this year at Ottawa on both European and American larches. 



Gossyparia spuria, Mod., is injurious to elms at Ottawa. The young appeared 

 in late June and early July. The leaves below badly infested branches are some- 

 times entirely covered with a thick coating of wax. This must render the leaf 

 practically useless and contribute towards the weakening of the tree. 



Kaliosysphinga dohrnii, Fisch., is common about Ottawa on native and culti- 

 vated alder. It occurs on several exotic species in the Arboretum in immense 

 numbers, and quite spoils the appearance of the trees. 



Pemphigus acerifoUi, Eiley. An aphis, probably of this species, was particu- 

 larly troublesome this year at Ottawa on ornamental maples. During July winged 

 and wingless adults and young were in dense masses on the undersides of curled 

 leaves. Wlax filaments and drops of honey dew, whitened by wax, were constantly 

 dropping from the trees. 



Schizoneura americana, Eiley, was the cause of many enquiries from southern 

 Quebec and Ontario. 



Podosesia syringae, Harris, Avas found at Ottawa destroying stems of lilac. The 

 caterpillars were boring in the base of the stems, excavating the inner bark and sap- 

 vrood. 



Aegeria exitiosa, Say. A caterpillar, probably of this species, has been numer- 

 ous for some years in a grove of wild cherry at Isle Perrot, Que. Many of the 

 trees have been destroyed by it. Phloeotrihus liminaris breeds in these trees; but 

 to a limited extent, and appears not to be increasing in numbers. 



Galerucella decora, Say., was reported stripping willow and poplar at various 

 points in British Columbia. 



Tylonota himaculatus, Hald., was taken at Ottawa from ash. The larvae were 

 breeding in apparently sound wood. 



Cyllene robiniae, Forst, has been destructive in southern Ontario. Consider- 

 able injury was caused to ornamental acacias near Kingston, Ont. It is interesting 

 that while acacias were badly injured, locust trees were apparently not attacked. 



Pissodes. Various species of this genus have been injurious to spruce and pine. 

 The most interesting reports were from P.E.I. , and from the Eocky Mountain 

 Forest Eeserve, Alberta. In the latter place there is a rather serious outbreak of 



