MIMICRY OF SPIDERS. 47 



these spiders a good memory of the location of their domiciles, and a sense 

 of direction sufficiently developed to bring them upon the return path with 

 accurac}^ 



Of course there is nothing remarkable about this, for such facts are 

 true of the insect world generally. It is known by all bee hunters, and by 



all keepers of bees, that either the wild or the hive bee will find 

 ■^ its way home after a long excursion in search of honey. So 



also I have frequently observed the mud dauber wasp erecting 

 its clay cell upon a wall or building, making excursions to all points to 

 secure mud for her masonry, and invariably return with her mandible 

 hod full to complete her nidus. The same accuracy of memory, again, is 

 shown when, having finished her nest, she prowls through all the neighbor- 

 hood in search of spiders, winging her course to all points of the com- 

 pass, prying into nooks and crannies and out of the way places, mousing 

 under leaves and diving into flowers, and yet always directing her return 

 course without the slightest hesitation to her mud daub cell. It is need- 

 less to multiply such examples, and I only allude to them to show that 

 in this respect the spider is not peculiar, but is gifted, like other Arthro- 

 pods, with a memory sufficient for all the purposes of its life. 



III. 



Mr. F. M. Webster recently wrote me from tlie Ohio Agricultural Ex- 

 periment Station (February 17th, 1892) a note which contributes an inter- 

 esting item to the subject of mimicry as discussed Vol. II., 

 . Chapter XII., especially under Color Mimicry and Mimicry of 



Environment, page 367. A spider observed by him had mimicked 

 the white excreta of birds so perfectly as to deceive this thoroughly trained 

 and accurate observer. The color of the sjiider was whitish, with the 

 dorsal abdominal portion clouded with blackish, exactly resembling a mass 

 of bird droppings. The deception was further carried out by the spider 

 having spun a thin irregular sheet of white web on an elm leaf, in the 

 midst of which it was situated with legs drawn up. At the distance of a 

 few feet the observer was completely deceived ; he thought it the excre- 

 ment of a bird until he had the leaf in his hand. The appearance of 

 the semisolid mass within the white splash of semifluid matter was so 

 closely counterfeited, that Mr. Webster says he was truly provoked that 

 such an animal could so befool his eyes after all his years of training. 

 Judging from the general description sent, I infer the species to be our 

 old friend Misumena vatia, so famous both in America and elsewhere for 

 its color mimicry. 



Mr. Webster's observation is all the more interesting because of its exact 

 correspondence with one of which he was not informed until I called his 

 attention to it, which has received considerable attention from naturalists. 



