No. 2.] PROTECTIVE RESEMBLANCES IN SPIDERS. 107 



crops of some humming-birds full of small, soft-bodied spiders, 

 and many other birds feed on them. Stinging-ants, like bees 

 and wasps, are closely resembled by a host of other insects ; 

 indeed, whenever I found any insect provided with special 

 means of defense I looked for imitative forms, and was never 

 disappointed in finding them."* 



The ant-like species are probably protected by their 

 appearance from the attacks of many of the larger spiders. 

 We have kept great numbers of Attidte in captivity, and, 

 although they devoured flies, gnats, larvae, and other spiders, 

 they would never touch ants. Among spiders, however, as 

 among birds, we find that certain groups subsist almost entirely 

 upon ants.f 



The class of spiders whose mimicry protects them from 

 their enemies, whether they are birds or other spiders, probably 

 includes at least two of our own ant-like species, Synageles 

 picata and Synemosyna formica, which, in confinement, are 

 always hungry for gnats, but will not touch ants, even of small 

 size. 



The existence of a class of spiders which mimic the partic- 

 ular species of ants upon which they prey is not to be questioned, 

 but it is doubtful whether the benefit to the spider is increased 

 facility in capturing the ant, or whether it is merely protective. 

 It may be that the spider, by virtue of its resemblance to the ant, 

 not only gets an abundant supply of food, but also escapes being 

 eaten itself, and thus enjoys a double advantage. Both Bates 

 and WallaceJ take the ground that the advantage derived by 



*Loc. cit., p. 314. 



fDr. McCook tells me tkat L. formidahilis pitches her tent over or near the 

 formicary of the powerful agricultural or stinging-ant of Texas, P. barbartus, and 

 captures the Insects as they climb the stalks of ant-rice. He also says that T. tepi- 

 dariorum devours large numbers of ants, and he has seen them eaten by A. fasciata, 

 Simon also gives an interesting account of the depredations committed upon ants by 

 spiders of the genus Enyo, AracJm. de France, Vol. I, p. 2i3. 



tBates says ; "There are endless instances of predaceous insects being disguised 

 by having similar shapes and colors to those of their prey ; many spiders are thus 

 endowed." Lepidoptera of the Amazon Valley, p. 509; and Wallace : "There is a 

 genus of spiders in the tropics which feed on ants, and they are exactly like the ants 

 themselves, which, no doubt, gives them more opportunity of seizing their prey. " 

 Natural Selection, p. 98. 



