678 THE POPULAR SCIENCE MONTHLY. 



that intellectual greatness is " beset with mental and moral infirmity," 

 or that genius is merely an expression of a morbid mind, akin to mad- 

 ness. 



Imagination gives to genius — which is the intellectual scout of 

 progress, and the Titan force which organizes the factors of civiliza- 

 tion — a realm wherein the soul throbs and burns with the fervor which 

 comes only when a new truth cleaves the darkness and illumines a 

 pathway hitherto unrevealed ; and where the clash and turmoil of 

 cerebral action excite the highest pleasure, though at the same time 

 they often weary and exhaust. 



In this century, when the fierce blaze of modern thought has filled 

 the world with unparalleled glory, and the inventive genius of man 

 has made the earth a vast workshop of industrial arts, wherein the 

 human brain is " master-workman " over all, how rare is it that the 

 brain-worker feels the oppression of a " mind diseased," except when, 

 like the wage-worker, he frets and worries under the burdens of a 

 weary life, and falls by the wayside because the struggle for existence 

 — keen, sharp, and relentless — has taken from him the inspiration, the 

 strength of hope ! 



Mental stagnation, personal or domestic sorrow, social inthrallment, 

 religious excitement, crushed hopes, and poverty, are the chief moral 

 causes which contribute so largely to the mental infirmities of man. 



In conclusion, I hesitate not to say that the most illustrious names 

 of ancient or modern times — in all departments of human thought or 

 activity — have been, with but few exceptions, loyal to the sovereign 

 rule of sane reason ; and the sweep of their imagination has been in 

 curves which rounded in the bright empyrean of truth and beauty. 



ANIMAL-PLANTS AND PLANT-ANIMALS. 



By Dr. PFUHL. 



IF we examine the bright bow of Iris painted on the heavens by the 

 sunbeams that break through the parting storm-clouds, no matter 

 how closely we may scan it, we shall not be able to determine where 

 the colors begin or end. As in this arch the blue gradually passes 

 over into a green, and the green in turn changes insensibly into a 

 yellow, even thus we find, in the countless forms in which Nature 

 delights, the most delicate gradations, the most gradual transitions. 

 Natura non facit saltus : this saying of Linne's is realized every- 

 where in the ever-changeful realm of life. 



How difficult a matter it is to decide whether the lung-fish of 

 Brazil and Senegambia belong to the amphibia or to the fishes, which 

 in other instances are known to always breathe by their gills ! In the 

 rainless season of the year the swamps, the homes of these animals, dry 



