166 A NATURALIST IN HIMALAYA 



the sky and hide the face of Nature. Plains, whole 

 mountain ranges, even the very sun, ar^ blotted from 

 our view. At last the thunder-clouds burst ; torrents 

 of rain descend ; the veil of dust is swept to ground 

 and a new world is exposed. 



Animal life continues to flourish amidst this 

 chano^ino- scene. In the streams that rush down the 

 wooded slopes or flow more gently through the 

 rounded hills are many forms, all competing for the 

 right to live. Fresh-water crabs creep lazily through 

 the pools. They did not seem to struggle hard for 

 life, yet even these crabs had their own device by 

 which to seize their prey. One day I observed a 

 fresh-water crab eagerly devouring a dead frog. As I 

 never saw dead frogs floating in these streams, I 

 felt sure that the crabs must capture their prey alive. 

 They were not very active animals and usually 

 remained at the bottom of the pools, so I wondered 

 how they succeeded in catching the sharp and nimble 

 frogs. In another pool the little problem was solved. 

 On first searching the water for any sign of life 

 I detected nothing but a few tadpoles ; then, on 

 looking more carefully, I saw the tips of a pair of large 

 claws projecting from beneath a quantity of bright 

 green water-weed. Not a trace of the body was 

 visible ; nothing but the pair of limbs widely 

 separated, with the claws partly open, clearly showing 

 that the crab was lying in ambush to seize a passing 

 animal. There were no frogs in this pool, so I 

 removed one from the stream and gently lowered 

 it towards the extended claws. The crab immediately 

 darted from beneath its green hiding-place, clutched 

 the frog in its strong claws and scuttled away beneath 



