108 PECKHAM. [Vol. 1, 



the spider consists in greater ease in the capture of prey, but 

 both of these writers refer to spiders only incidentally to illus- 

 trate a general proposition, without special consideration of 

 their peculiar conditions. 



Mr. Herbert Smith, who has paid a good deal of attention 

 to this subject, is inclined to believe that the mimicry in ques- 

 tion is entirely protective. He writes as follows : 



" In the United States there are a few rare spiders that 

 mimic ants. Here at Taperinha we find a good score of species 

 of these spiders aping the various kinds of ants very closely ; 

 even the odd, spiny wood-ant, cryptocerus, furnishes a pattern, 

 and there are spiders that mimic the wingless ichneumons. We 

 find, after awhile, that the spiders prey upon ants just as our 

 spiders catch flies ; indeed, this fact has already been noted by 

 other observers. But we go a step beyond the books when we 

 discover not only that the spiders eat the ants, but that they 

 eat the particular ants which they mimic. At all events, we 

 verify this fact in a great number of cases, and we never find 

 the spiders eating any but the mimicked species. * * * j 

 do not like to hazard a theory on this case of mimicry. It is 

 difficult to suppose that the quick-witted ants would be deceived 

 even by so close a resemblance ; and, in any case, it would seem 

 that the spiders do not require such a disguise in order to 

 capture slow-moving ants. Most birds will not eat ants; it 

 seems likely, therefore, that this is simply another example of 

 protection ; the spider deceives its enemies, not its prey ; it 

 mimics the particular species that it feeds on, because it is seen 

 in that company when it is hunting, and among a host of 

 similar forms is likely to pass unnoticed." * 



At first sight, and especially in view of the fact that such 

 cases are not uncommon among insects, it would be naturally 

 supposed that the object of the mimicry was to enable the 

 spider to approach its victim without exciting suspicion ; and it 

 is difficult to account, on any other supposition, for the very 

 close resemblance between certain species of spiders and the 



* Loc. clt., p. 223. 



