So far as is known these insects undergo no changes during the 

 winter, but when the sap begins to flow freely in the spring the young 

 scales which survive resume their feeding on the sap which was 

 interrupted by the cold weather and complete their growth, becoming 

 adult in June. Reproduction then begins, the young being born alive, 

 and this continues for about six weeks, each female producing an 

 average of about 400 young. The young insects are very small, and 

 after their birth, crawl out from beneath the scale where they were 

 born and move about, seeking a place on which to settle. This takes 

 rather more than a day, on an average, and during this time these 

 tiny, yellow, crawling young may be seen wandering about. On find- 

 ing a good location they become quiet and each works its long beak 

 through the bark, (or surface of the leaf or fruit as the case may be,) 

 to where the sap of the tree can be obtained and the insect sucks this 

 sap for its food. Its legs now disappear, its body becomes hemi- 

 spherical, and white, waxy threads appear over its back. These 

 mat together to form a white covering or scale, and such young,, 

 recently formed scales are often very noticeable. Later as the insect 

 grows it molts or sheds its skin and the molted skin is added to the 

 scale which because of this and by weathering becomes darker, gray- 

 ish or even blackish, often showing rings of lighter and darker 

 color. The center of the scale is the highest point and around this 

 is a circular depressed ring. If the insect beneath the scale is a 

 female the scale will remain nearly circular in outline ; if a male, the 

 scale is more oval or elongated in form. In a little more than a 

 month from the time of its birth the insect becomes adult and in turn 

 begins to produce young, the first ones appearing at about the same time 

 as the last ones of the preceding generation. These young develop 

 in the same way as did their parents, thus giving a constant success- 

 ion of young from the middle or end of June, in Massachusetts, till 

 winter stops the process. 



It is evident that the increase in numbers of this insect is very 

 great : estimates on this point show that an average of 1,608,040,200 

 females would be produced from a single female in one season, with 

 probably at least an equal number of males, a total starting from a 

 single female of 3,216,080,400 individuals! This estimate makes 

 no allowance for loss by accidental destruction, but this is undoubt- 

 edly very great and is probably the main reason why we yet have 

 any fruit trees alive, and it is fortunate that winter kills so many of 

 the scales. 



