life's borderlands 247 



ology you are astonished at the contrast between the few sea 

 animals from the Arctic regions and the bewildering array of 

 t>T>es from the tropical seas. Corals of many sorts, some of 

 them of huge size; enormous shells, both conchs and clams, 

 the latter sometimes weighing thousands of pounds; immense 

 sea-urchins and equally large star-fishes; crabs and shrimps of 

 scores of different kinds; and a vast assortment of other things. 

 You naturally conclude that life is much more abundant in the 

 tropics than it is in the north. I have examined many coral 

 reefs in different parts of the world, but compared with the 

 incredible abundance of animals on very cold bottoms or on 

 the northern coasts where the bottom is suitable, tropical reefs 

 appear singularly barren. True, the number of different kinds 

 of animals on the reefs, corals, shells, star-fishes, anemones, sea- 

 urchins, sponges, crabs, worms, etc., is enormous, vastly greater 

 than the small number of kinds in the cold sea; but the ac- 

 tual bulk of all the animals taken together is very much less, 

 and there are no such Uving animal carpets such as we often 

 find in the north. 



Yet there are a number of animals that enjoy remarkably 

 high temperatures. The larva of a stratiomyid fly is re- 

 ported to have been found in a hot spring in Gunnison county, 

 Colorado, in water with a temperature of 157° F. In a hot 

 spring in Uinta county, Wyoming, the larvae of a stratiomyid 

 fly were found in water so hot that the hand could not be 

 held in it, the estimated temperature being not more than 20° 

 or 30° below the boiling point. In hot springs in Owen's 

 Valley, California, a spider-like animal and small red worms 

 were found in water having a temperature of 124°. The little 

 crustacean known as Cypris has been reported from hot springs 

 with a temperature of 122° F., while microscopic ciliated animals 

 and rotifers have been found in water of which the temper- 

 ture is given as 149° F. In the Yellowstone Park a little insect 

 known as Salda was seen running about the edges of springs 

 which were actually boiling, and two species of an insect called 

 Nehria were found living under pieces of geyserite even on the 



