438 MAINE AGRICULTURAL, EXPERIMENT STATION. IQI2. 



median and second lobes, two laterad of the third pair of plates, two 

 laterad of the fourth pair of plates and one laterad of the fifth pair of 

 plates. There is a seta on each basal margin of the median lobes, one 

 between the lobules of the second lobes, one just byond the first and 

 second pairs of marginal pores, and one between the plates of the fifth 

 pair. The dorsal pores are as shown in figure 478. There are five 

 groups of circumgenital pores as follows : 



9 9 II 12 



16 21 18 21 1516 1715 

 1513 9 ii 1415 '13 12" (Herrick 1911) 



Life history. This insect has long been known in this country, 

 though believed to be a native of Europe. In June the eggs, 



/ ulml 



FIG. 478. 



which are found under the scale of the old female, hatch, the 

 active young appearing as small specks which soon attach them- 

 selves to new shoots by their beaks. The scale then begins to 

 form gradually increasing in size. As with the San Jose scale 

 the adult male is provided with both wings and legs. 



The scale occurs nearly everywhere in the United States as 

 well as in other parts of the world, and may be found on a 

 variety of plants. The apple, pear, plum, cherry, currant, wil- 

 low, elm, birch, butternut, dogwood 1 , ash, oak, linden, poplar, 

 and rose being particularly affected. 



It is the most common scale on the apple in Maine. 



Remedies. As the insect winters in the egg stage it is quite 

 resistant to sprays, yet experience has shown that when lime- 



