vicinity, and from various sections of Illinois, Indiana, Wisconsin, and 

 Iowa. It is interesting to note that most of the reports of serious 

 injury by this insect come from those States or portions of States north 

 of the fortieth parallel, where it seems to be attacked by fewer parasites 

 than in the southern regions. A map of its distribution prepared by 

 the author from locality cards shows that it is distinctively an Upper 

 Austral zone species but occasionally reaches the Transition zone. 



The cottony maple scale is classified in the soft, unarmored group 

 (Non-Diaspina?) of the family Coccidas, and does not differ superficially 

 from the Lecaniums, except in the formation of an ovisac by the female 

 of the Pulvinaria. The male insect is a very small and delicate two- 

 winged fly which develops its latter stage under a glassy test or covering 

 and emerges late in August or early in September. 



FOOD PLANTS. 



The various species of maples, particularly the soft maple {Acer 

 saecharinum) , including the box-elder (Acer negundo), are the favorite 

 food plants of this species. The writer has, however, found it on 47 

 different species of trees, shrubs, and vines, including various species 

 of maple, oak, linden, elm, willow, poplar, beech, hawthorn, sycamore, 

 locust, hackberry, osage-orange, mulberry, grape, poison-ny, apple, 

 pear, plum, peach, currant, gooseberry, rose, and Virginia creeper. It 

 is possible that a very careful study will prove that all these infestations 

 are not referable to one species, but that other species may be separated 

 just as the maple-leaf Pulvinaria [P. aeericola (Walsh and Riley)] and 

 the osage-orange Pulvinaria [P. maclurce (" Kenn.," Fitch)], once con- 

 sidered identical, were found to be distinct from the cottony maple scale. 



HABITS AND LIFE HISTORY. 



The large, white, flocculent masses, resembling popcorn fastened to the 

 twigs, which appear on infested trees during the month of June, arc the 

 cottony (really waxy) ovisacs of the female, provided for the retention 

 of the eggs after oviposition (fig. 1). These may contain as many as 

 1,500 minute, oval, pale reddish-yellow eggs. 



The larvae hatch at various dates from June 1 to August 15, depend- 

 ing on the latitude and exposure to the sun's rays. After remaining in 

 the ovisac for a day or two, they swarm over the twigs, instinctively 

 migrating toward the light, and settle on the leaves along the midribs 

 and veins, always preferring the under surface (fig. 2, e). The larva' 

 on box-elder become active somewhat in advance of those on maple. 

 This difference may be due to the food, but it must be remembered that 

 the shade of the box-elder is less dense than that of the maple, and 

 consequently the greater amount of heal and light may be the con- 

 trolling factor. The male larva 1 , when fully grown, assume a propupal 

 Stage from which they pass to the true pupal stage having a pinkish 



