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uoiis ; not so in insects, here they occupy an equal footing 

 with those which they destroy. The parasites of the army 

 worm are quite numerous. There is at least one of the 

 Diptera, the Senometopia militaris, Walsh. And among 

 the Hymenoptera, wo find Ophion purgatus, Mesochorus vU 

 trens, Walsh ; Pezomachus minimus, Walsh ; Microgaster 

 militaris, Walsh ; Ichneumon Leuccmice, Fitch ; and one or 

 two others figured in the last edition of Harris under the 

 article on the army worm. The Chalcis albifrons, Walsh, 

 is parasitic on Pezomachus minimus ; and G]yp)he viridas- 

 cens, Walsh, on another ichneumon ; thus are counter- 

 checks brought to bear upon the checks themselves. The 

 Calosoma Calidum, though not a parasite, destroys a great 

 many of the caterpillars. 



But not only are insects our friends, but also the birds 

 greatly benefit us, far more tlian enough to pay for the 

 harm they do. The army worms are eaten greedily by all 

 our black birds, crows, robins, &c. So let our interest cry 

 mercy witli our pity, and protect our beautiful feathered 

 friends. 



In spite of all these natural checks, we see that some- 

 times the insects are permitted to increase beyond their 

 place, and it becomes necessary for us to protect ourselves 

 against them. I will now therefore proceed to consider the 

 methods which have been found the most effectual for keep- 

 ing them in check, and protecting our crops from them. 



If it is true that they lay their eggs in Summer near the 

 roots of the grass, we have all the knowledge of their econ- 

 omy we need to enable us to fight against them in the sur- 

 est way ; we know every stage ol their life, and have only 

 to find the best means of attacking them in the different 

 circumstances under which they present themselves. 



It appears from Mr. Walsh's investigations, that the best 

 time to destroy these insects is at the beginning of their ex- 

 istence, while they are still in the egg ; all that is necessary 

 to accomplish this result is to burn the fields in the dead of 

 the year ; by so doing all the eggs in the grass are burned, 

 and the fields are much improved, the old stubble is re- 

 moved, while the ashes contain all the chemical constituents 

 which would be left if the stubble was allowed to decay in 



