NESTING HABITS AND PROTECTIVE ARCHITECTURE. 309 



in part, be seen upon the webs of our two large indigenous species of 

 Argiope. On either side of the orb these spiders are in the habit of 

 throwing out wings of crossed Hues, which extend, as a rule, be- 

 Protect- j^^.^^Ij ^i^q lower margin of the hub upon which the spider ordi- 

 narily hangs, thus securing industrial protection from every di- 

 rection except from below, which point is guarded by the defensive organs 

 and armor. In point of fact, Argiope thus encloses herself within a rude 

 tent of straggling lines. These lines ward off assailants, or check or en- 

 tangle them, and give warning of danger in time to escape. Their purpose 

 is manifestly protective, since they are apparently too open to serve for 

 catching prey, and otherwise do not seem adapted to that end. The Or- 

 chard spider, Argyroepeira hortorum, resorts to the same mode of protec- 

 tion, but, inasmuch as she makes a horizontal web and hangs upon the 

 under part thereof, the protective apron is thrown beneath the orb, and 

 thus secures the aranead against the approach of enemies from the ex- 

 posed quarter. 



5. The central shield of thick spinningwork, which is found beneath 

 the Banded and the Basket Argiope, may also be regarded as protective; 

 and it is probable that the thick scalloped and pointed ribbon decorations 

 characteristic of the Banded Argiope and also of Uloborus, serve some pro- 

 tective purpose besides the strengthening of the net. At least, it is the 

 habit of the spider to place herself behind these screens, which thus pro- 

 tect her from the exposed point, the shrubbery and other objects against 

 which the snare is fastened being the protection from the other side. 



6. Another protective use of simple lines may be seen in the case of 

 the Hunchback orbweaver, Epeira gibberosa, who makes a hammock tent, 

 swung between leaves. She spins a series of straight lines quite thickly 

 between the edges of a leaf, or several leaves, and hangs underneath them, 

 communicating with her snare by the usual taut trapline. She is thus 

 protected beneath and on all sides by her leafy site, and above by her 

 hammock. 



7. In addition, and generally, it may be said that almost all the orb- 

 weaving families will avail themselves of any chance cavity or projection 

 for temporary shelter or as a permanent site. Therein they hide them- 

 selves, either with or without additional protection of spinningwork, and 

 remain until appetite prompts them to spin their snares and place them- 

 selves upon them to procure food. In some cases, as with the Furrow 

 spider, such a shelter is habitually preferred ; a hole or depression, or even 

 more frequently a dry curled leaf or bit of bark, being chosen. 



In point of fact, spiders appear to live continually in dread of enemies, 

 and their whole life is spent in a defensive industrial warfare for the pro- 

 tection of their persons, or in offensive war upon those insects which fur- 

 nish them their natural foo<l. In the former case they are habitually in 

 hiding; in the latter, in ambush. 



