NATURE STUDY LESSONS. I TQ 



boys "take turns." A channel is cut around au oblong 

 perhaps a foot by a foot and a half in extent, leaving a 

 big chunk of ice intact. At last the axe is driven through 

 at some part of the channel, and now it is better that a 

 grown-up take a hand. For the water is rushing upward 

 as from a tiny geyser, caused bv the pressure of the ice 

 upon the surface of the pond. A few quick strokes in the 

 splashing water releases the chunk of ice, which may now 

 be heaved out, in the midst of increasing excitement, for 

 it is more than likely that already a spn,- whirligig or a 

 blundering dytiscus has seen the opening and hurried to 

 come up to the light and air. 



Every boy and girl knows the Whirligigs, the active, 

 smooth, fiat, black beetles, whose family name, Gyrinidse, 

 refers to their habit of going round and round on the sur- 

 face of the water, where they gather in thick clusters or 

 patches and appear as if thej- had all gone crazy at once. 

 They are fond of air and sunshine, and. when the ice be- 

 gins to melt, they find the ver\' first holes that appear and 

 begin hurrying round and round in the bits of water as if 

 in wild delight that spring has come. In the same wa}', 

 when a hole has been cut in the ice, there will almost al- 

 ways be a Whirligig on hand by the time the fragments 

 of ice have been scooped out. The Whirligigs, when held 

 in the hand, have a peculiar, not wholly unpleasant smell, 

 as of apples just beginning to deca3', suggestive of or- 

 chards and the heaps of pomace near cider-mills. They 

 have four legs that are flattened, like oars, for swimming, 

 while the front legs are fitted for grasping the tiny live 

 things that the}- feed upon. Their eyes seem to be doub- 

 le — one pair looking upward and the other looking down- 

 ward, so that the Whirligig can have an e3'e for ene- 

 mies above and for food below at the same time. There 

 are usualh' at least two kinds, or species, in any pond or 

 brook, but the differences are slight, and it is enough for 



