151 



Strickland (E. H.). The Cottonwood Leaf-mining Beetles in Southern 

 Alberta.— C'a«a(/. Entom., London, Onf., lii, no. 1, Januarv 1920, 

 pp. ]-5, 4 figs. 



Zeugophora scutellaris, Suft'r., and Z. ahnormis, Lee. (cotton wood 

 and poplar leaf-mining beetles) are responsible for much damage in 

 Alberta and Saskatchewan to cottonwoods and other poplars that have 

 proved to be the best species for shade and ornamental purposes in 

 those regions. Z. scutellaris appears in the adult stage feeding on 

 the leaves about 15th June, and from that date until the end of the 

 month its numbers increase rapidly. The beetles are generallv most 

 abundant on the smaller-leaved varieties of cottonwood and are 

 always more numerous on the sheltered side of the tree and on trees in 

 sheltered situations. Towards the end of the month mating occurs, 

 and within a few days eggs are deposited within half an inch of the leaf 

 margin where^ the veins are very fine, several being laid in one leaf 

 but many failing to hatch. Soon after oviposition, the tissues above 

 the egg-cavity turn brown. The larvae, immediately upon hatching, 

 begin to enlarge the cavity in which they have hatched, feeding on 

 the leaf cells just under the upper epidermis. This causes the lower 

 tissues of the leaf to turn black, the discoloration showing through the 

 transparent upper epidermis. A large blister made by the tunnels 

 of various larvae may contain many individuals, though only one 

 usually survives. By mid-September most of the larvae are mature, 

 and break through the thin upper surface of the leaf to fall to the 

 ground. After burrowing some inches below the surface they 

 construct a cavity in which they hibernate. 



Z. ahnormis is rarely seen on cottonwood but is abundant on balm of 

 Gilead {Populus halsamifera). The life-history is similar in both 

 species, but as many as 50 eggs of Z. abnormis may be laid in a single 

 leaf ; about 28 per cent, of these fail to hatch, the larvae are more 

 gregarious and as many as seven healthy individuals have been found 

 in one blister. The greatest damage is to foliage 6 to 10 feet from the 

 ground and is always worst on sheltered trees ; leaves towards the 

 centre of the tree are seldom attacked. Z. abnormis does not occur 

 annually in such large numbers as Z. scutellaris, but in some years is 

 very abundant on the comparativel}- small numbers of its food-plant. 



Egg-parasites of both species are numerous, particularly a Mymarid 

 reared from Z. abnormis. Over 40 per cent, of the eggs contained 

 various stages of this parasite. Sprays of 1 oz. Paris green and 4 oz. 

 slaked lime to 10 gals, water gave better results than lead arsenate ; 

 the spray must be directed to the underside of the leaves with an angle 

 nozzle, and should be applied as soon as the beetles appear in any 

 numbers. Spraying operations must be general, owing to the powers 

 of flight of the beetles. 



Takahashi (R.). a new Genus and Species of Aphid from Japan. 



(Hera.).— Camrf. Entom., London, Ont., lii, no. 1, January 1920, 

 pp. 19-20, 1 fig. 



For a new Aphid that has been found in the leaves of Podocarpus 

 macrophylla, the genus Neophyllaphis has been erected ; it is compared 

 with Phyllaphis, Koch, to which it is closely related. The type species, 



