ENEMIES AND THEIR INFLUENCE. 401 



ignorance, and which, I am thankful to record, is yielding before the 

 light of modern science. In truth, the spider is not only a harmless creat- 

 ure as far as man is concerned, but is, on the contrary, a most helpful 

 one to him in many respects. She is one of those checks established in 

 the economy of Nature against the increase of insects whose presence 

 would make the world well nigh uninhabitable by the human species. 



Some idea of the destruction wrought in the insect world by the cun- 

 ningly devised snares of Orbweavers may be had from the following facts : 

 I have counted nearly two hundred and fifty insects, small and great, hang- 

 ing entangled in one web. In another net, in Fairmount Park, I counted 

 thirty-eight mosquitoes ; in another, hung under a bridge at Asbury Park, 

 and out of reach, there must have been tWo or three times as many. 

 Greenhead flies by the legion have been seen in the snares that fairly en- 

 lace the boat houses at Atlantic City and Cape May. Very small spiders 

 prey upon microscopic insects, like gnats, and devour myriads. A glance 

 at the fields, bushes, and trees on a dewy morning in September will reveal 

 an innumerable multitude of webs spread over the landscape, all occupied 

 by spiders of various ages, sizes, and families, and all busy destroying the 

 insect pests of man. These webmaking spiders thus revealed are only a part 

 of the numberless hosts engaged in this friendly service. On the ground, 

 in crevices and crannies into which man never looks; lurking on flowers, 

 on leaves, on limbs and twigs of trees^ shrubs, grasses; in barns, cellars, 

 outhouses; everywhere, indeed, upon the face of Nature, one who will take 

 the pains to look will find legions of spiders carrying forward day and 

 night without cessation tlie same vigilant and unrelenting warfare upon 

 the insect world. They are of all sizes and of various forms ; in all stages 

 of their life, from the spiderling upon its tyro web to the grizzly veteran 

 just ready to give up its life as the frosts of autumn fall. If one stops 

 to consider that all these creatures must find food, and do find food, and 

 that the chief supply is furnished from the realms of insect life, he may 

 form some faint conception of the destruction which is wrought, and, by 

 consequence, the service done to man. 



To the testimony thus gleaned from field observations we may add the 

 evidence of postmortem examination made by a careful and learned stu- 

 dent with the aid of the microscope. Dr. C. Keller, of Zurich, 

 Arachne claims that spiders perform an important part in the preserva- 

 Porest *^°'^ °^ forests, by defending the trees against the depredations 

 Keeper. ^^ aphides and insects. He lias examined a great many spiders, 

 both in their viscera and by feeding them in captivity, and has 

 found them to be voracious destroyers of these pests ; and he believes that 

 the spiders in a particular forest do more effective work of this kind than 

 all tlie insect eating birds that inhabit it. He has verified his views by 

 observations on coniferous trees, a few broad leaved trees, and apple trees. 

 An important feature of the spiders' operations is that they prefer shaded 



