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 observations that 

 at least a part of the insects remain on the trun'< of the apple 

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

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

 ning 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 

 newly 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 

 a 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 

 :o the surface and go ofit" to find a suitable place to se<:ure food. 



CONFUSED WITH THE WOOLLY APHIS. 



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

 fettle on newdy 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 

 »' as able to be sure of the identity of the mealy-bug only by break- 

 ."np; apart the flocculent matter and examining the bodies them- 

 selves. 



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 

 which is about ^ of an inch long. With all secretions removed 



