1903] 



Gibson — Hunting for Caterpillars. 



79 



at the base allow of this net beings easily held by taking" the upper 



bar in the left hand, so that the lower bar rests against the back 



of the wrist. We have used 



these nets in connection 



with our official field work 



and have found them very 



serviceable. Dr. Fletcher 



has recommended them in 



his departmental reports 



as of much value in col- 



lecting various insects 



which are troublesome 



to the market gardener, 



etc., so that they can be 



afterwards destroyed. 

 J B 



There are many kinds of caterpillars, however, which cannot 

 be collected by beating, or gathered from beneath stones, bark, 

 etc., on the ground. Some of these are borers, which pass 

 the whole of their larval existence feeding inside the stems 

 and roots of various plants. The caterpillars of the genus 

 Papaipema {Hydroecia) have, within the last few years, been given 

 special attention by some students. These larvae are true borers 

 and work within the stems of burdock, goldenrod, etc. Papai- 

 pema cataphracta, which bores in burdock, is a common species 

 at Ottawa wherever the plants are numerous, and the presence of 

 the caterpillar can usually be detected by the withering and dis- 

 colouring of the tips. The caterpillars ot P. appassionata^ which 

 have only recently been discovered, were found, by Mr. Henry 

 Bird, ot Rye, N.Y., feeding in the roots of the Pitcher-plant {Sar- 

 racenid). Last season, when at the Mer Bleue, the writer exam- 

 ined many pitcher-plants, but could not find any larvae, although 

 in the root of one plant the work of a noctuid caterpillar was de- 

 tected, as well as some frass, but of course we do not know that 

 it was of this species. 



Other larvae of smaller species of moths form various kinds 

 of cases, inside of which they live and change to the pupal state, 



