41 
to our observation, elsewhere in Illinois. Wherever it appears it 
multiplies locally, but makes a slow spread, a fact apparently due to 
the sluggishness of the parent beetle, which, although provided with 
wings, makes extremely little, if any, use of them. In consequence 
Pig. 43. Small poplar tree in Chicagi) showing dying of upper 
brandies re-ulting from attacksof the Poplar and Willow Borer, 
Cryptorhynch.us lajmttd. 
of this fact, an infested grove may be nearly destroyed before an- 
other, near at hand, becomes even infested. It extends its range 
most readily along watercourses by means of the willows and cot- 
tonwoods with which our streams are likely to be fringed. Its 
spread to distant points seem to have been mainly, if not altogther, 
by way of the nursery trade, especially that in poplars and willows 
of various kinds. These facts make it particularly important that 
