46 



twelve species occur abundantly in New England, tlu*ee more extend 

 nearly or quite as far south as the Great Lakes and the St. Lawrence, 

 and two or three are found in California; three occur in, or are inti- 

 mately allied to others inhabiting the Rocky Mountain region near our 

 own parallel, and one of them has been previously described only 

 from central Siberia. On the whole the fauna does not seem to be a 

 distinctive one, but to unite in itself the characters of the elevated 

 portions of the whole of boreal America, from ocean to ocean, and, in 

 part, those of the neighboring portions of the Asiatic continent; the 

 foundation, however, is formed of types characteristic of the great 

 interior of the continent north of the United States. Judging by the 

 specimens brought home, the three most abundant species are Papillo 

 Turnus, Pieris venosa and Papilio Aiiaska', and it is a little remarka- 

 ble that each of these species is characteristic of one of the three great 

 divisions, — eastern, western and central boreal America. 



