MONTANA EXPERIMENT STATION. 129 



HABITS OF THE ELM MEALY-BUG. 



We have learned but little of the life-history of the species found 

 at Missoula but it is probable that it is similar to that of the maple- 

 inhabiting species. However, it is plain from our observatioivs that 

 at least a part of the insects remain on the trunV of the apple 

 throughout the summer. In fact, though, we were often in the orch- 

 ard in Missoula where this insect occurred in 1902, frequently run- 

 inng across clusters of the insects under the scales of bark, we did 

 not in a single instance find any of them on the leaves. Occasionally 

 we found the partly grown female insects crawling about the limbs 

 and twigs but never attached and feeding except on the trunk. Un- 

 der the scales of bark the insects were invariably found under the 

 rewly formed scales where the bark was of a light color and thin. 



The habit of the females in the spring of the year to cluster 

 about the buds of the elm as shown in the accompanying figure, is 

 B. prominent one though we did not detect any injury done in this 

 way. As the female insect feeds and grows she produces a very 

 light and soft cottony mass about herself which is pure white. On 

 coming to maturity the insect deposits her eggs in this cottony 

 mass. When the young hatch from the eggs they work their way 

 to the surface and go off to find a suitable place to secure food. 



CONFUSED WITH THE WOOLLY APHIS. 



It is a well known habit of the areal form of the woolly aphis to 

 f^ettle on newly made scars on the trunks of apple trees taking their 

 nourishment through the tender tissues to be found there. This 

 mealy-bug was found affecting apple trees in the same manner. So 

 similar are the cottony masses of the two insects that the writer 

 >' ns able to be sure of the identity of the mealy-bug only by break- 

 ing apart the flocculent matter and examining the bodies tlicm- 



s elves. 



-DESCRIPTIONS. 



The male and female mealy-bug are very unlike in appearance. 

 The male Is , very delicate and has long transparent wings, long legs, 

 and long antennae. Its size is much less than that of the female 

 \yhich is about j>^ of an. inch long. With all secretions removed 



