y\6 



THE POPULAR SCIENCE MONTHLY. 



and shows his teeth. When properly treat- 

 ed, the otter is easily converted into an 

 affectionate and playful pet. He is a trifle 

 larger than a cat, having a very similar 

 head, only flatter, which is provided with a 

 fine set of teeth, and he can use them with 

 terrible force for his size. On his lip he 

 has a lot of strong bristles. His eyes are 

 small and have a watchful look about them ; 

 the neck is almost as thick as his chest; his 

 body is long and round ; the legs are very 

 short, strong, and flexible ; the toes webbed 

 for a great part of their length, and the 

 claws on them sharp. The tail is thick at 

 the root, and tapers off to a point. It is 

 very powerful, and is, in fact, his swimming- 

 machine. In color he is dark brown, as a 

 rule, with the sides of his head and throat 

 brownish gray. On land the otter moves 

 with a peculiar loping gait. When he comes 

 up out of the water, there is first a little 

 swell on the surface, then his head appears, 

 and if everything is quiet he silently crawls 

 up on a log or bank. When startled, he 

 makes one gliding plunge, and the water 

 closes over him with scarcely a ripple. 



The Yalne of Daman Variation. — Mr. 



Francis Galton, addressing the Anthropo- 

 logical Institute recently, said that anthro- 

 pologists ought to give more consideration 

 to variety than they have hitherto bestowed 

 upon it. They commonly devote their in- 

 quiries to the mean values of different 

 groups, while the variety of the individuals 

 who constitute those groups is too often 

 passed over with contented neglect. An 

 average man is morally and intellectually 

 a very uninteresting being. The class to 

 which he belongs is bulky, and no doubt 

 serves to keep social life in motion. It also 

 affords, by its inertia, a regulator that, like 

 the fly-wheel to the steam-engine, resists 

 sudden and irregular changes. But the aver- 

 age man is of no direct help toward evolu- 

 tion, which appears to our dim vision to be 

 the primary purpose, so to speak, of all 

 living existence. Evolution is an unresting 

 progression; the nature of the average in- 

 dividual is essentially unprogressive. Ilis 

 children tend to resemble him exactly, 

 whereas the children of exceptional persons 

 tend to regress toward mediocrity. The 

 Hebrew race, whose average worth is not 



especially notable, is mainly of interest on 

 account of its variability, which in ancient 

 and modern times seems to have been ex- 

 traordinarily great. It has been able to 

 supply men, time after time, who have 

 towered high above their fellows, and left 

 enduring marks on the history of the world. 

 In a mob of mediocrities, the general stand- 

 ard of thought and morals must be medi- 

 ocre, and, what is worse, contentedly so. The 

 lack of living men to afford lofty examples 

 and to educate the virtue of reverence would 

 leave an irremediable blank. All men would 

 find themselves at nearly the same dead 

 average level, each as meanly endowed as 

 his neighbor. These remarks apply with 

 obvious modifications to variety in the physi- 

 cal faculties. Peculiar gifts, moreover, af- 

 ford an especial justification for division of 

 labor, each man doing that which he can do 

 best. 



The Interdependence of Life. — The doc- 

 trine of the dependence of life on external 

 conditions, says General R. Strachey, includes 

 life itself as an important concurrent agen- 

 cy in the general results observed. Thus, 

 in order to supply the food and other require- 

 ments of animals, the presence of vegeta- 

 bles or other animals is necessary. To some 

 animals, as well as to some plants, the shel- 

 ter of forests or particular forms of plants 

 is essential. Parasites need for their sus- 

 tenance living plants and animals. The fer- 

 tilization and hence the propagation of plants 

 is a development of life not deviating in any 

 particular direction from that which follows 

 the hereditary principle. It rather appears 

 that the existing face of nature is the result 

 of a succession of incidents, unimportant in 

 themselves, which by some very slight al- 

 teration of local circumstances might have 

 been turned in a different direction. For 

 instance, a difference in the constitution or 

 sequence of the substrata at some locality 

 might have determined the elevation of 

 mountains where a hollow filled by the sea 

 was actually formed, or the converse, where- 

 by the climatal and other conditions of a 

 particular area would have been changed, 

 and a different impulse there given to the 

 development of life. All that we see or 

 know to have existed upon the earth has 

 been controlled to its most minute details by 



