PART V -HOSTILE AGENTS : THEIR INFLUENCE. 



CHAPTER XII. 

 MIMICRY IN SPIDERS. 



The subject of mimicry among spiders, as with other animals, is most 

 interesting and yet most difficult to treat. I accept the word as one gen- 

 erally used among naturalists, to express certain resemblances, more or less 

 complete, between a spider and surrounding objects in Nature. I do not 

 include within the word the idea that the volition of the spider controls 

 these resemblances, except in a very limited degree, which will hereafter 

 be pointed out. The theories of the origin of mimicry, which have been 

 discussed by many naturalists, appear to me to rank little higher than 

 more or less ingenious suggestions unsupported by facts sufficient to justify 

 them as scientific inferences. But at present this condition of things 

 seems unavoidable, and by patient and careful accumulation of facts chaos 

 may at last yield to order and well defined law. 



Among spiders the various kinds of mimicry may be divided into the 

 following : First, industrial mimicry of plants and other objects or envi- 

 I'onment; second, form mimicry of animals; third, form mimicry of envi- 

 ronment; fourth, color mimicry; fifth, cocoon mimicry; and sixth, death 

 mimicry. The .last of these will be considered in another connection. 



I. 



The most remarkable examples of industrial mimicry of surrounding 



objects are to be found among the Trapdoor spiders, as recorded in the 



charming pages of Moggridge, some of whose figures I have 



Industrial |i,y^glj^ well to reproduce in Plate II. of this volume. These 



imicry .^j^jjj^^jg^ which make burrows in the earth, whose ojienings are 



ronment ^^losed by doors swung upon a hinge of thickened silk, are in 



the habit of covering tlie outside of their doors with dry leaves 



or living moss, so that they resemble the surrounding site, in which thej- 



are placed so closely that even Mr. Moggridge, when looking for them, 



was often deceived. 



Perhaps in no case is the concealment more complete than when dead 

 leaves are employed to cover the door. In some instances a single witliered 

 olive leaf is placed in to cover the trap. In others several leaves are woven 

 together with bits of wood and roots, as seen at Plate II., Figs. 1 and 2, 



(352) 



