SPIDERS NESTS. 



jerked out of the hole. If, however, as often happens, an insect 

 who has the misfortune to fall from the brink of the precipice 

 should recover itself, and escaping the murderous jaws of its enemy 

 regain the summit, the latter immediately begins to throw up 

 more sand, whereby not only is the hole made deeper, but its sides 

 are rendered more precipitous, and the flying insect is often hit 

 by the masses thus projected, and brought down again to the 

 bottom. 



19. Certain spiders spread snares still more singular. The 

 web which these animals spread is destined to catch the flies 

 and other insects upon which they prey. The disposition of 

 the filaments composing this web varies with different species, 

 but is often of extreme elegance. 



20. There are certain fishes which feed upon insects that are 

 not inhabitants of the water, and who resort to expedients, bearing 

 marks of great ingenxdty, to capture their prey. Thus, a species 

 called the Archer, which inhabits the Ganges, feeds on insects 

 which are accustomed to light upon the leaves of aquatic plants. 

 The fish, upon seeing them, projects drops of water upon them 

 with such sure aim, that it seldom fail? to make them fall from 

 the leaf into the water, when it seizes upon them. As the near 

 approach of the fish would alarm the insect and cause its flight, 

 this species of liquid projectile is usually launched from a distance 

 of several feet, where the insect cannot see its enemy. 



21. Certain species feed upon natural products, which are only 

 to be found at particular 

 seasons of the year ; and 

 in all such cases Nature 

 prompts them, during their 

 proper harvest, to collect 

 and store up such a quan- 

 tity of food as may be suffi- 

 cient for their support, 

 untU the ensuing season 

 brings a fresh supply. The 

 common squirrel (fig. 4.) 

 presents an example of 

 this instinct. During the 

 summer these active little " 

 creatures collect a mass of 

 nuts, acorns, almonds, and 

 other similar products, and 

 establish their storehouse 

 usually in the cavity of a 

 tree. They have the habit of providing several of these magazines 



121 



Fig. 4. — The Common SquirreL 



