222 PHYSICAL GEOGRAPHY. 



In 1 854, Prof. L. Agassiz made the first attempt* to divide North 

 America into several zoological areas ; and, on a rude map accompanying 

 his sketch, he draws a line in an east-westerly direction, which passes 

 through New Hampshire. The two great regions thus separated he 

 names the Canadian and Alleghanian faunas. 



In 1859, Dr. J. L. LeConte divided the United States into a number of 

 "entomological provinces;"! and the "northern" and "middle" provinces 

 of his "Atlantic district" were separated by a line which passed through 

 the southern half of New Hampshire. 



In 1863, Prof. A. E. Verrill also pointed out that the dividing line of the 

 Canadian and Alleghanian faunas cut New Hampshire in two,t and three 

 years later he defined the Hmits more exactly as "coincident with a line 

 which shall indicate a mean temperature of 50° Fahrenheit during the 

 months of April, May, and June;" and, in describing its course, says,— 

 "It passes south of Moosehead and Umbagog lakes, but rises somewhat 

 northward along the Androscoggin valley, thence it passes southward of 

 the White Mountains, through the vicinity of Conway, N. H. It bends 

 northward again up the Connecticut valley as far as Craftsbury, Vt., where 

 the mean temperature is 50° 91." H 



Mr. J. A. Allen has recently discussed the areas of the faunas of east- 

 ern North America ; and, in his description of the northern boundary of 

 the Alleghanian fauna, says the line "follows the northern boundaries of 

 the lowlands through southern Maine and southern New Hampshire. In 

 the Connecticut valley it rises farther to the northward, and, in its south- 

 ern descent, skirts the eastern base of the Green Mountains." § 



Both of these latter writers base their conclusions upon the study of 

 birds during breeding season, as first suggested by Prof. Verrill, in 1866, in 

 the paper from which we have quoted, and where he further writes, — "From 

 this remarkable coincidence between this system of lines of temperature 

 of the months of spring and early summer, with what had been already 

 observed in the actual distribution of birds, we must necessarily infer 



* Nott and Gibbon: Types of Mankind, p, Ixxviii, and map. 



f The Coleopteraof Kansas and Eastern New Mexico. Smiths. Contr. 4to, 1859. 



X " The Adirondack region of New York, ths northern parts of Vermont and New Hampshire, including most of 

 the higher parts of the Green Mountains and all of the White Mountains, and even the summits of the higher 

 AUeghanies, will be included in the Canadian fauna," Froc. £ss. last., iii, 138. 



I Proc. Bast. Sue. Nat. Hist., x, z6o. 



? Bull. Mus. Comp. Z06I., ii, 395 (1871). 



