Ivi LLOYD'S NATURAL HISTORY. 



while, as the insects found there are not handsome enough 

 to command a correspondingly high price. Yet they furnish 

 many interesting species, which are ordinarily difficult to obtain. 

 Such countries are Chili, the Canaries, Madeira, and New 

 Zealand. But in the case of some of these localities, as also 

 in others, the help of friends abroad may sometimes be use- 

 ful. 



ON THE GEOGRAPHICAL DISTRIBUTION OF BUTTERFLIES. 



Butterflies are distributed over the surface of the earth in 

 very unequal proportions, and are most numerous where the 

 vegetation is most varied. As a general rule, in Europe and 

 Asia they are most numerous along the great ranges of moun- 

 tains in the warmer countries, thinning rapidly both north and 

 south, and towards the west. 



The regions of Geographical Distribution in use by most 

 recent Zoologists are those proposed by Dr. P. L. Sclater in 

 his paper on the Geographical Distribution of the Class Aves.* 

 I subsequently published a paper on the Geographical Dis- 

 tribution of Diurnal Lepidoptera,f following the same system ; 

 and it was also adopted by Dr. Alfred Russel Wallace in 

 his important work on the Zoological Distribution of Animals, 

 though he suggested a division of each of the large regions 

 into four sub-regions. 



The provinces adopted by Dr. Sclater are, roughly, as follows : 



/. Paltzarctic Region. 



Includes Europe, the Mediterranean Region, North Africa 

 to the Sahara, and Asia, except India south of the Himalayas, 

 South China, and islands south of Japan. 



* Journal of the Linnean Society of London, Zoology, vol. ii., pp. 130- 

 145. 

 * Ibid., vol. xi. pp. 431-439. 



