PROTECTIVE RESEMBLANCES IN SPIDERS. 



ELIZABETH G. PECKHAM. 



Introduction. 



There are, among spiders, two forms of protective modifi- 

 cation : the first, including all cases of protective resemblance 

 to vegetable and inorganic things — that is, all modifications of 

 color or of color and form that tend to make them inconspicu- 

 ous in their natural relations — I shall call direct protection. 

 The second form, which I shall call indirect protection, includes 

 two classes, the spiders which are specially protected themselves 

 and those which mimic other creatures which are specially 

 protected.* 



Spiders are specially protected when they become inedible 

 through the acquisition of hard plates and sharp spines. The 

 modification of form is frequently accompanied by conspicuous 

 colors, which warn their enemies that they belong to an unpal- 

 atable class, t 



The second class of indirectly protected spiders — those 

 that mimic specially protected creatures — presents some difficul- 

 ties, since it is not always easy to determine whether the pur- 

 pose of mimicry is protection or the capture of prey. The 

 resemblance may, as is frequently the case in direct protection, 

 serve both purposes. 



In looking for instances of protective form and color 

 among spiders we encounter one difficulty at the outset. The 



* Wallace classifies tlie colors of animal organisms as follows : 



1. Protective colors. 



•> WarnlTia- pnlnr=i <■ "• O* creatures specially protected. 



-. warning colors, j j_ qj defenseless creatures mimicking «. 



3. Sexual colors. 



4. Typical colors. 



Tropical Nature and Other JSssays, p. 172.. 



t Under special protection would also fall cases, sucli as are common among other 

 animals, of the development of some nauseous taste or odor; but we know of no sucli 

 case among spiders. 



