COMPOSITE SNARES AND SECTORAL ORBS. 



135 



and, indeed, may be described as the method which Agalena also uses when 

 spinning the retitelarian supports of her long sheeted snare. 



The peculiar snare of LabjTinthea and other spiders making a composite 

 web appears to be a larger development of a habit which is seen to a greater 

 or less degree in the genus Argiope. In considering the particular 

 A Devel- gpinningwork of this genus I have already called attention to the 

 fact that both Cophinaria and Argyrasi>is suspend the upper foun- 

 dation lines of their orbs to a series of intersecting straight lines 

 which are spun with more or less consistency to the overhanging and sur- 

 rounding foliage. This sys- 



oped 

 Habit. 



tern of crossed lines is very 

 frequently carried downward 

 to one side of the orb and 

 sometimes upon both sides, 

 so that it forms what I have 

 called the protective wings or 

 fenders. If the reader will 

 compare the more i)erfect and 

 permanent spinning habit of 

 Labyrinthea and Triaranea with 

 that which is described and fig- 

 ured as the work of Argiope, he 

 will see the close resemblance be- 

 tween the two. One may therefore 

 say that what appears as a rudimentary 

 habit, or a habit more or less developed in 

 the case of Argiope has appeared as a per 

 veloped and fixed habit in the S2:)inning behav 

 rinthea. There is a marked peculiarity in the fa 



Labyriuthea chooses for her snare. This 

 Q-, dead and leafiess bush, or a leafless part of 



branch. The habit is quite persistent, and I 

 every well established habitat of the species. ' It is true 

 spin her snare among leaves, but her preference is for a 

 obstructed. In such sites she is often seen in little 

 nies. In one such colony at Radnor, Pennsylvania, I 

 adult spiders, whose snares were spun upon a dry no. 120. cobp- brush heap 

 within a space six feet long, six wide, and five f"*'^"'' J"""^^" high. To 



A o' ' keeping by two ° 



this " clearmg " every individual settler had no Labj-rinth spi- doubt been 

 attracted by the same favorable conditions for an un *'^^' obstructed 



habitation. Perhaps the instinct which induces this choice is under the 

 same influence as that which urges many Theridioid species to seek similar 

 sites for their retitelarian snares, which exactly resemble the maze of Laby- 

 rintliea's web. Certaiuly, it is interesting and curious to find these two 



ectly de- 

 ior of Laby- 

 vorite site that 

 is noticeably a 

 a tree or dead 

 have seen it in 

 tliat she will 

 locality not so 

 groups or colo- 

 counted tliirtv 



