. An annotated list of the important North American forest insects. Forest insects. in Chicago that the egg-contents of 80 to 85 per cent of the cotton}' ovisacs had been destroyed by the white mealy larvse of Hyperaspis. These larvte enter and devour the entire contents of one ovisac after another without destroying its form, so that onlj' an examination will reveal the empty ones. The predaceous caterpillar of IxefUia cocciclii'ora Comst. has been an efficient ally in controlling the pest in the vicinity of Washington, D. C. It is particularly effective where the cottony masses are in close
. An annotated list of the important North American forest insects. Forest insects. in Chicago that the egg-contents of 80 to 85 per cent of the cotton}' ovisacs had been destroyed by the white mealy larvse of Hyperaspis. These larvte enter and devour the entire contents of one ovisac after another without destroying its form, so that onlj' an examination will reveal the empty ones. The predaceous caterpillar of IxefUia cocciclii'ora Comst. has been an efficient ally in controlling the pest in the vicinity of Washington, D. C. It is particularly effective where the cottony masses are in close prox- imit3% because of its habit of eating its way through the masses, spin- ning a strong web about itself, and forming a gallery as it progresses. The caterpillar is very active and moves about freely within its web. Several specimens of Leucopis nigricornis Egger, a common dipterous parasite of aphides, were reared from cottony maple scale collected in Chicago, 111., on July 21, 1905, by the writer, and from other specimens sent to the Bureau from Crystal Lake, 111. This parasite is considered to be a European species, and although aphides seem to be its favorite host, it is occasionally reared from nondiaspine Coccidae. Several species of chalcid flies (Chalcidoidea) are trulj^ parasitic upon the cottonj' maple scale as well as upon others of the Lecaniina?. There is no doubt that many more Pulvinarias are killed by these interesting little fellows than b}- all other enemies. Coccophagus lecanii Fitch, C. flavoscn- tellum Ashm., Atropates colUnsi How., Aphycns pulvhiarue How., Comys fusca How., and Eimoins lividus Ashm. have been reared from the cottonj' maple scale. Fig. Z.—Pxilvinaria innn- merabilis: gravid fe- male, greatly enlarged, before commeneing to secrete egg sac in tlie spring (from Howard). In dealing with an infestation by the cottony maple scale, the most important matter to be considered in each case is the advisabilit}^ of artificial means of
Size: 999px × 2501px
Photo credit: © Library Book Collection / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookauthorhopkinsadandrewdelmar, bookcentury1900, bookdecade1900
