110 THE REPORT OF THE No. 19 



have a great variety of food plants, among which are the various kinds of 

 China and German asters, dahlias, and some other Compositae. As a rule 

 Blister Beetles only do damage in years following excessive locust outbreaks. 

 In their larval state, as is well known, they are predaceous parasites on the 

 eggs of grasshoppers, and therefore when the beetles appear in numbers it 

 is undesirable to destroy them if this can be avoided. Although the attack 

 is generally severe while it lasts, the period during which Blister Beetles 

 injure vegetation is not of long duration, and, besides this, they do not occur 

 injuriously every year. Like other leaf-eating insects, however, these beetles 

 can be destroyed by spraying the plants with a Paris green, or other arsen- 

 ical, mixture. In small gardens a simpler remedy is to beat them into a pan, 

 or other shallow vessel, containing water with a little coal oil on the top. 



T^. ,_ r^i X, i.1 Fig. 46. Rose beetle. 



V Ai Hi ■ A ^^' Flea-beetle. * 



Blister-beetle. " '"'^^ (^^"^^ enlarged.) 



Flea-Beetles. (Fig. 45.) The foliage of some kinds of garden plants 

 is often partly, or wholly, devoured by small active beetles, which leap like 

 fleas, owing to which habit they are known by the name of flea-beetles. 

 There are a number of different species in Canada, two of which specially 

 are responsible for much damage. In early spring at Ottawa, the white 

 flowers of the favorite border and rockery plant, Alpine Rock Cress, Arahis 

 alpina, L., are nearly every year injured, some seasons very seriously, by 

 Phyllot/eta vittata, Fab., which, on account of its great destructiveness to 

 tlie leaves of turnips, is called the Turnip Flea-beetle. The perfect beetles 

 are about one-eighth of an inch long and in color are black, shining, with 

 yellowish marks on the wings. On several occasions the Red-headed Flea- 

 beetle, Systena froixtalis, Fab., has been the cause of much injury in the 

 Botanic Garden of the Central Experimental Farm. (Report Entomologist 

 and Botanist, Dom. Exp. Farms, 1889.) Young plants and low shrubs of a 

 great many orders were attacked, their ravages being particularly to some 

 species of AJthcca, Hibiscus and Weigelia. Injury was all done by the per- 

 fect beetles, few plants appearing to come amiss to them. This flea-beetle 

 is about one-fourth of an inch long and has a black head with a red patch on 

 the top of the head in front. In August last the beetles were very abundant 

 at Ottawa, particularly on the second crop of clover. Another flea-beetle 

 which has not yet been identified is occasionally destructive at Ottawa to 

 Forget-me-nots. Paris green and land plaster, or flour, in the proportion of 

 one pound of the former to twenty of the dry diluent, dusted on infested 

 plants, if possible when they are covered with dew, is one of the best reme- 

 dies against these troublesome insects. The ordinary poisoned Bordeaux 

 mixture is particularly effective against flea-beetles when applied as a 

 spray, and indeed has been found to be by far the best remedy for controlling 

 the Potato Flea-beetle, Eyitrix cucumeris, Harr. 



The Rose Beetle, Macrodactylus suhspinosus, Fab. (Fig. 46.) This 

 common enemy of the fruit-grower, known also as the "Rose-chafer" and 

 'Rose-bug," which every year does so much harm in vineyards and orchards. 



