. Cottony maple scale (Pulvinaria innumerabilis Rathvon.). Scale insects; Pulvinaria; Agricultural pests. in Chicago that the egg-contents of 80 to 85 per cent of the cottony ovisacs had been destroyed by the white mealy larvae of Hyperaspis. These larvae enter and devour the entire contents of one ovisac after another without destroying its form, so that only an examination will reveal the empty ones. The predaceous caterpillar of Lcetilia coccidivora Comst. has been an efficient ally in controlling the pest in the vicinity of Washington, D. C. It is particularly effective where the cottony m
. Cottony maple scale (Pulvinaria innumerabilis Rathvon.). Scale insects; Pulvinaria; Agricultural pests. in Chicago that the egg-contents of 80 to 85 per cent of the cottony ovisacs had been destroyed by the white mealy larvae of Hyperaspis. These larvae enter and devour the entire contents of one ovisac after another without destroying its form, so that only an examination will reveal the empty ones. The predaceous caterpillar of Lcetilia coccidivora 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- imity, 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 Lencopis 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 truly parasitic upon the cottony maple scale as well as upon others of the Lecaniinse. There is no doubt that many more Pulvinarias are killed by these interesting little fellows than by all other enemies. Coccoplmgus lecanii Fitch, C. flavoscit- tellum Ashm., Atropates collinsi How., Aphycus pulvinarice How., Comys fusca How., and Eunoius lividus Ashm. have been reared from the cottony maple scale. Fig. 3.—Pulvinaria innu- •merabilis: gravid fe- male, greatly enlarged, before commencing to secrete egg sac in the spring (from Howard). In dealing with an infestation by the cottomT maple scale, the most important matter to be considered in each case is the advisability of ar
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