190 



AA^ ECONOMIC ENTOMOLOGY. 



applied with a knapsack pump through a Vermorel nozzle, and 

 a little Paris green adds greatly to its effectiveness. It should 

 be renewed every week or two until the middle of July, when the 

 danger from these flat-headed borers may be considered at an 

 end, and it has the advantage of protecting the branches as well 

 as the trunk. The admixture of a little glue or salt wiU improve 

 its adhesive and lasting qualities. 



A strong fish-oil soap, say one pound in one gallon of water, 

 is also effective and may be applied in the same manner. It 

 forms a film of soap over the bark, and is repellent to the beetles 

 as well as fatal to the young larvae. The admixture of an ounce 

 of crude carbolic acid to a gallon of suds is advantageous. This 

 mixture should not be applied to leaves or on young shoots, 

 as it would probably cause injury. As these methods are all 

 preventive rather than remedial, they must be promptly and 

 thoroughly applied, and success will be in proportion to the 

 thoroughness with which the work is done. Instead of any of 

 the preceding methods, "insect lime" or "dendrolene" may 

 be with proper precautions employed on the trunks and larger 

 branches, and, practically, this is the best material for use against 

 the "sinuate pear-borer." It can be easily applied, remains 

 effective for weeks, and one application, properly made at the 

 right time, will protect the trees for the season. As against the 

 pear-borer, it should be applied not later than May 15th, and 



are no species injurious to vegetation, though, under the name 

 "fire-flies," some of them are well known. The beetles are 

 usually slender, somewhat flattened above, with a more or less 

 retracted head, and are of a soft leathery texture. The ' ' fire- 



FiG. 175. 



kept intact until June 

 15th, when all danger 

 from that pest is over. 

 Reference should be 

 made to the chapters 

 on insecticides and 

 preventives for further 

 details as to applica- 

 tions. 



Fire-fly, Photinus pyralis.—a, larva ; b, pupa in cell ; 

 c, adult ; dto/, structural details of larva. 



In the next series, 

 the Lampyridce, there 



