148 ■ BOARD OF AGRICULTURE. 



those localities. So there are insects frequenting mountains that 

 are not found in the vallies below. More lepidoptera inhabit the 

 summits of high mountains than beetles and other insects. In 

 Maine there arc found species which inhabit the sea coast alone, 

 others that abound most on the sandy plains that run back from 

 the sea to meet the hills of the interior, and some of the most pro- 

 ductive places are those towns situated on the border of the low 

 lands and hilly- regions of the State. Other species are found only 

 in the thick forests of the wild lands. * 



Moreover it has been found that two assemblages of insects 

 called /awnae, people the surface of the State. The one called the 

 Canadian fauna comprises a large mass of species that inhabit 

 British North America, the Great Lakes, and the lakes and forests 

 of northern Maine, including Eastport and the coast towards Mt. 

 Desert. The other assemblage called the Alleghanian fauna, is 

 that which covers the southern half of the State, besides New- 

 England generally, (except the White Mountain region which be- 

 longs to the Canadian fauna,) and sweeps down the Alleghany 

 range towards the southern States. The plants of the summit of 

 Mount Katahdin belong to a more arctic region still than the Can- 

 adian flora ; whether the insects partake of the subarctic character 

 remains to be determined. 



Hymenoptera. 

 In studying this suborder we must remember that every part of 

 the body varies in furra in the different genera, forming admirable 

 and plain distinctions to characterize the genera. To the form of 

 the head and its appendages, that of the thorax and its appendages, 

 the wings in the venation of which we can perceive at a glance 

 those characters which separate genera, and in the legs especially of 

 the fossorial families, where there are found to be great difl'erences, 

 the student must look closely. The best specific characters lie in 

 the sculpturing and color, but the spots and markings are apt to 

 vary greatly. The great diflerences in the sexes are liable to mis- 

 lead the student, and hence large collections are indispensible to 

 their proper study. The Hymenoptera are the most numerous in 

 species of all the suborders except the Coleoptera. They have 

 been less studied- in this country than almost any other suborder, 

 though so deserving from their interesting habits. Especial atten- 

 tion should be paid to collecting the smaller species, and to the 

 families of the Chalcididae, the Gynipidae and the Crabronidae. 



