THE INSECT FAUNA OF MOUNT DESERT, MAINE 



INTRODUCTION 



The study of the insect fauna of a given section, aside from 

 its purely entomological importance, has great economic value 

 in showing the relative distribution of the injurious species 

 and their parasites. It also presents many biological features 

 of general interest bearing on distribution, variation, the 

 relation of insects to the flora, and other environmental 

 conditions. 



The value of such a study is often greatly enhanced by 

 being made in a region so favorably situated as to show- 

 clearly many of the factors governing distribution. In this 

 respect there are probably few places that equal Mount 

 Desert. Situated on the southern edge of the area defined as 

 the Canadian life zone or the most southern extension of the 

 Boreal region and the most northern extension of the so-called 

 Transitional zone of the Austral region, it forms a meeting- 

 ground of the northern and southern species. 



As I am endeavoring in this paper to show as far as it is 

 possible the relation of insects to the flora, I will first consider 

 what the botanists say regarding plant distribution.^ "One 

 of the most marked characteristics of the island flora is its 

 not only strongly northern, but arctic character. On its coast, 

 enveloped in cold fogs and washed by waters chilled by the 

 arctic currents, it is no wonder that arctic plants like Montia 

 fontana and Stellaria humifusa should find a congenial home. 

 Moreover this character of the flora is shown by the fact that 

 with one exception, Lycopodium selago, the mountain plants 

 descend to the sea level. Neither on the one hand is the alti- 

 tude of the mountain summits sufficient to develop an alpine 



^"A preliminary catalogue of the plants growing on Mount Desert," by Ed- 

 ward L. Eand and John H. Redfield, p. 20, Cambridge, 1894. 



