HORIZONTAL SXARES AND DOMED ORBS. 



157 



The next most common species of Tetragnatha is the Stilt spider, 



Ti-tragnatha grallator Hentz. 1 In color the adult is not so brilliant as 



Extensa, being a dull gray; but in its general form, habits, and 



^ the structure of its web it corresponds with Extensa, but is 



larger, darker, and less attractive in appearance when adult. It 



differs, also, in its greater fondness for a location near or over water. Its 



webs are frequently seen stretched above the surface of running streams. 



In pools, in the quiet nooks of brooklets and creeks, where branches droop 



down from the banks and overhang the water, I often find a colony of 



v I kvh I ' * ' .-.-=? 



FIG. 149. Horizontal orb of the Stilt spider, stretched above a brooklet (Doe's Run). 



Stilt spiders that have spun their horizontal orbs upon the leaves and 

 twigs close down to the water's face. As the wind moves the branches 

 to and fro the webs almost dip into the stream beneath. Here the crea- 

 tures hang and prey upon the insects that always frequent such sites in 

 great numbers and hover over the stream. (Fig. 149.) 



Another favorite position is underneath the boards and cross logs of 



1 T. elongate Walck., Nat. Hist. d. Ins. Apt., ii., page 211. Dr. Thorell has little doubt 

 that Hentz's species T. grallator is identical with Walckenaer's T. elongata. See ''Aranese 

 of Colorado," Bulletin U. S. Geolog. Surv., 1877, page 479. 



