INTRODUCTION. 85 



the Equator there being no wolves, he refers the dogs in the Old 

 World to the jackal, &C, in the New World to the Aguani fox dogs. 



We have been thus particular on the subject of the dogs, as 

 they have been triumphantly appealed to as arguments in favor of 

 the unity of the human races; they certainly show little positively 

 in favor of this view, and much negatively against it. 



lint, even among animals, there is a very great difference in their 

 capacity for variation, which renders any argument that might be 

 drawn from them of little value. The mouse, lor instance, shows 

 very little disposition to change, in color or form ; the brown rat of 

 Persia, now spread over the world, very nearly preserves its original 

 type. According to Dr. S. G. .Morton, (Proc. Acad. Nat. Sciences, 

 Phil., April, 1850,) the reindeer of Lapland do not change in the 

 slightest particular after long domestication ; the peacock has not 

 varied for thousands of years. Some animals, in two or three gen- 

 erations, are entirely changed in color, as tin- Guinea-pig and tur- 

 key; sometimes even the anatomical structure changes, as in the 

 pigeon, sheep, and dog ; some animals, even in the wild stale, 

 undergo great changes, e.g., the fox-squirrel, (Sciurus captstratus,) 

 whose black variety is not to be confounded with the unchanging 

 Schtrtu niger. The tiger is the same in tint, under considerable 

 rariety of climate, from Siberia to Ceylon. In the province of 

 Delhi, Bishop lleber saw a shaggy elephant ; he Bays that in one or 

 two winters dogs, and even horses, brought from Europe, become 

 woolly in that region, whose men are remarkable for the length and 

 Btraightness of their hair. Dr. Morton also remarks that the wool 

 of sheep becomes Ion? and hairy in Guinea, where human hair is 

 wiry and twisted. So that the causes which change the lower ani- 

 mals, do not alTect man. In this respect one animal is not an ana- 

 logue even for another animal, still less is an animal an analogue for 

 man. 



If the races of man are analogous to the varieties of animals, 

 why does not he, under similar circumstances, tend to a uniform 

 type? Why do not these varieties occur before our eyes among eiv- 

 i/it'il /nan, who has been called the most domestic of animals? and 

 the more frequently as civilization, with its many unnatural accom- 

 paniments, makes progress ? The capacity for variation may explain 

 temporary varieties of men and animals, but it cannot account for 

 the permanent ran' tics, or species. 



The characteristics most relied on for the discrimination of the 

 races are ttie color of the skin, the structure of the hair, and the 

 conformation of the skull and skeleton. There are several evident 

 types of these marks in the races; the transition, however, is so 



