216 BULLETIN NO. 62. 



NATURAL HISTORY. 



The life history of this important insect was first worked out 

 hy Benj. D. Walsh and published in 1866, (Vol. 5 of Practical En- 

 tomologist). Other facts have been added by more recent writers, 

 notably, Prof. C. P. Gillette, Dr. C. Y. Riley, Prof L. Bruner. The 

 facts contained in these papers have been in a large measure veri- 

 iied for Montana. 



TIME OF APPEARANCE. 



The beetles appear early in the spring of the year, and feed on 

 the buds and flowers, having spent the winter under some suitable 

 shelter in the vicinity. Prof. Gillette records having taken beetles 

 in Iowa as early as April i6th, or fully one week before the trees 

 were in bloom. Allowing for backwardness of season, due to our 

 altitude and elevation, for parts of Montana other than the Yellow- 

 stone Valley, Bitter Root Valley and the Flathead country, we may 

 ■look for the beetle, when it becomes generally distributed, at about 

 the tenth to fifteenth of May, and in the lower Yellowstone, Bitter 

 Root and Flathead valleys, about two or three weeks earlier. The 

 time of appearance of the adults is of practical importance because 

 of the fact that at this season, and while the eggs are being deposit- 

 •ed, is the only opportunity to effectively combat the pest, except 

 hy the laborious and inadequate method of hand-picking the infest- 

 •ed fruits. 



EGG LAYING. 



After the young fruits have set and begun their growth the 

 females deposit their eggs in them, eon egg in a plum, first boring 

 a hole with the snout to receive the egg. The egg is placed just 

 below the surface of the skin and is yellowish white in color, with 

 no external markings. It is nearly spherical in shape, measuring 

 one thirty-fifth of an inch in greatest dimension. On exposure, 

 after being laid, the egg changes to a jet black color. 



Many more wounds are made in the fruit than required for the 

 egg. These wounds all appear throughout the growth of the plum 

 on the tree. Many punctures are often found on a single plum. 

 The flesh grows less perfectly near the wound, resulting in a depres- 



