MIMICRY IN SPIDERS. 371 



responds with the entrance of the little fellows into life, and that the pe- 

 riod of flowering is contemporaneous with their growth. It seems neces- 

 sary, in order to sustain consistently the tlieory of survival, that a j^ellow 

 spiderling should have a yellow environment from the outset, and that 

 a white and pink spider should have a corresiJonding site from exode 

 to maturity. But, in point of fact, when we find the adult Misumena 

 upon a half opened rose, as in the cases above mentioned, we know that 

 the rose was opened up but yesterday, whereas the spider must have been 

 several weeks in maturing. This is true of all cases, or certainly of most 

 cases, in which we find adult spiders domiciled or ambushed upon flowers. 

 We are therefore compelled to the conclusion that the color did not 

 nourish the spider by providing for it a protective site, but that the 

 spider sought the flower and settled upon it, either accidentally or of 

 choice. 



Epeira parvula is a spider remarkable for the variations it presents 

 in the dorsal markings of the abdomen. It is widely distributed through- 

 out the United States from ocean to ocean, and everywhere has 



^ , the same characteristic. I have usually found it upon its orb 

 parvula. . . . . 



waiting for prey, but like other Epeiras it undoubtedly rests 



upon adjacent objects. The Peckhams cite this sj^ecies as an example of 

 protective resemblance in spiders.^ It is a common spider in Wisconsin, 

 and the Peckhams most frequently saw it on cedar bushes, where its color 

 harmonizes with the color of branch and fruit. During the day it usually 

 rests on the branch near its web. The back of the abdomen is a peculiar 

 bluish green, exactlj^ like that of the lichens growing on tree barks. The 

 bluish color is broken up by waving black lines, which imitate the curl- 

 ing edges of the lichens. I reproduce the drawing given by the Peckhams 

 to illustrate this resemblance. (See Plate III., Fig. 5.) Undoubtedly, the 

 resemblance in this case is striking, but I take it to be simply an accident 

 of the situation. Parvula is found everywhere and upon all sorts of foli- 

 age, even where cedar bushes and lichens are not found. It is necessary 

 to remember this, although, of course, it does not gainsay the fact that 

 among Wisconsin cedar bushes it may have received some benefit from the 

 resemblance which the Peckhams note. 



The suggestion has been raised tliat there may be some protective 

 value in the brilliant metallic colors which are possessed in a high de- 

 gree by some species of spiders. I have no observations to offer 

 „ , on the subject, but quote a remark of Mr. A. G. Butler, of 



the Kensington Museum. He says that metallic colors are not 

 a source of protection from birds, as birds know nothing of the nature of 

 metal, and whatever is brilliant and shining they make for at once, to see 

 whether it is good to eat.^ 



• Observations on Sexual Selection, page 8.3. ' Jour. Royal Micros. Sec, 1889, page 633. 



