Turner, Notes Upon the Gallery Spider. 97 



Example IV. — Location: a railroad embankment, covered 

 with large cinders and weeds. Main sheet irregular, inclined, 

 extending from a large cinder upwards to several weeds Gal- 

 lery near one of the corners, penetrating the main sheet from 

 below. Guard web absent. 



The main sheets of all the webs so far considered are irreg- 

 ular in outline.. This is not always the case. The main sheets 

 of many webs have definite outlines, the outlines being deter- 

 mined by the environment. The triangular web is the com- 

 monest form. These are found in corners everywhere. 



These triangular webs are sometimes horizontal, sometimes 

 inclined toward the apex, sometimes inclined toward the foot. 

 The following examples may serve as types of many.. 



Example V. Location : angle between stone wall and 

 wooden post. Main sheet horizontal, attached in the angle be- 

 tween the wall and post. Gallery in the angle. Guard web 

 practically absent. Snares few. 



Example VL — Location: angle between two logs. Main 

 sheet inclined, passing from the apex of the angle upwards and 

 outwards at an angle of about five degrees. Gallery at the apex 

 of the triangle at the lowest point of the web. Guard web ab- 

 sent. Snares abundant. 



Example VIL — Location: angle between window-sill and 

 side wall. Main sheet attached in the angle between the pro- 

 jecting window sill and the side wall. The sheet slopes gradu- 

 ally downward along the side wall. Gallery in the angle. 

 Guard web, highest at the lowest point of the web. Snares 

 abundant. 



These I have called types. But the introduction of a new 

 element in the environment is sure to call forth a modification 

 to meet the case at hand. For example, if a ledge be near, a 

 portion of the web is almost certain to be extended along that 

 ledge for a short distance. 



The two following adaptations are further illustrations of 

 the same thought. 



Example VIIL — Location : angle between window-sill 

 and side wall. Main sheet horizontal, attached to the window 

 and to the side wall. Above this web there was a web of an- 

 other spider of the same species. A tension string united the 



