ARGIOPE AND HER RIBBOXED ORB. 



105 



Fenders 

 or Pro- 

 tective 

 Wing's. 



lines spun on either side or in front of the or!) at the distance of one or 



more inches from it. In certain positions these wings are thrown on either 

 side of the orb, as represented at Fig. 96, where the web is 

 hung within a conical or pyramidal mass of cross lines, a retite- 

 larian web, in fact. In this snare both the upper and lower sec- 

 tions of the orb were attached to strong foundation lines set 

 witliin this mass, which was itself attached to the surrounding 



foliage. This structure appears to be common as to the upper half of the 



orb, but the lower part is frequently fastened directly to tlie foliage or 



other objects of the site. Such an arrangement adds to the elasticity of 



the snare, and must materially contribute 



to its powers of resistance. When the 



webs of Argiope are spun in such a i)0si- 



tion as to expose the spider from either 



side, the wings are thrown out on both 



sides, as in the figure. But in a great 



number of cases only one side is thus de- 

 fended, and it will be found in such cases 



that the other side is protected by the 



foliage against Avliich the orb is spun. 



These fenders or wings are by no means 



universal. Indeed, I have examined scores 



of snares on the same day and for several 



successive weeks without noticing one ex- 

 ample. The Banded Argiope makes the 



same kind of protective wings, and I have 



found several half grown individuals of 



this species on the seashore of Cape Ann, 



Massachusetts, whose webs were all thus 



characterized. Sometimes the fenders are 



wholly separated from the spinningwork of the orb itself, and are thrown 



out well upon the flank, and attached to projecting i)arts of the foliage. 



They then commonly consist of very strong thick lines resembling those 



spun for -the foundation of the snare. 



The purpose of this outlying s})inningwork is probably protective. 



The scaffolding of crossed lines is thrown over both faces of the orb like 



wings, chiefly over the middle and up})er parts, thus covering the point 



where the spider domiciles. The wings are several inches distant from 

 the orb. Any large hostile insect or other enemy hovering around 

 tlie web must first touch the outlying wings, whose agitation 

 telegraphs a warning to the occupant. The detention resulting, 



trifling as it would be, might yet allow sufficient time, in many cases, for 



the occupant to escape. The protective wings might even hai)pen to ward 



Fig. 96. Protective wings or fenders of 

 Argiope's snare. (Side view.) 



Uses of 

 Wings. 



off wholly some assailants. On such provisions as this often hangs the 



