THE CANADIAN ENTOMOLOGIST. 163 



my own writings that I have chiefly borrowed from, the use of quotation 

 marks is unnecessary, the more so as I have here gone freshly over the 

 subject, digesting my previous observations and adding new ones before 

 preparing the present chapter in a history of our North American Lepi- 

 doptera. Some of my views, as here stated, were put forth in a lecture 

 I held in 18S5, before the Bremen " Naturwissenschaftlichen Verein." I 

 shall be glad if this paper adds to the interest naturally evoked by this 

 field of study in Natural History. 



It is a curious thought that our butterflies and moths have very pro- 

 bably remained unchanged, to any great extent, for real aeons of time. 

 These little fringes to the great web of animal Ufa have withstood the 

 tooth of time, while the pattern itself has been frayed out in places and 

 replaced. It is not unlikely that our Libythea £ac/ivia?iii^ itself may 

 have sported about the now long extinct Mastodon, alighting on the huge 

 back of this great beast as it sunned itself by summer pools in the willow- 

 hedged meadows and low lands. At the close of the Tertiary we have 

 evidence that our butterflies and moths were much the same as they are 

 to-day — not always the same species, nor the same genera, perhaps ; and 

 some of the kinds of these little fluffy ornaments may well have been 

 worn away by the cold and storms of the slowly advancing Ice Period. 

 But the pre-glacial ancestors of the present lepidopterous fauna of the 

 Northern Hemisphere must have greatly resembled their descendants of 

 to-day, while in the ranks of the larger animals great changes were to 

 occur. While in size, structure and appearance these butterflies and 

 moths of the Tertiary probably resembled those of the Quarternary, they 

 were to undergo the vicissitudes of a general change in the climate under 

 which we cannot believe but that they were forced to the South and the 

 great separation of the faunas took place, their former Arctic sporting 

 ground being converted into the frozen wilderness which it is yet so largely 

 to-day. At the opening of the Quarternary the migration commenced to 

 set back, but the conditions of climate under the Tertiary have never 



* I chose this species not only on account of the fact that I believe it to be a very 

 ancient form of butterfly, but because I found it very plentiful in Alabama about swampy 

 places on the roadside, from whence the species flew up in numbers to play in the air, 

 some settling on my horse in a particularly fearless manner, allowing me to catch one on 

 the very reins I held in my hand. This species is rare and solitary in New York, and 

 illustrates what 1 have to say here about the increase in munbers of certain species as we 

 go southward. 



