Turner, Notes Upon the Gallery Spider. 103 



stone wall and the post. In this case there is no hole in the 

 post, but there was a crack between the post and the wall in 

 which the gallery might have been hidden. Guard sheet practi- 

 cally absent. 



The spider that constructed this web was a member of the 

 same species as the spider that constructed the web recorded in 

 example V. Here again we have an example of individuals of 

 the same species, under similar circumstances, constructing dis 

 similar webs, and here again we have an example of something 

 that transcends instinct. 



We now come to consider variations in the morphology of 

 the guard sheet. In some cases it is absent. In horizontal 

 webs it is more often absent than present. According to my 

 observation, in horizontal webs, the ratio of the times present to 

 the times absent, is as one is to two. When the guard sheet is 

 present in horizontal webs, it may be either low or high. Com- 

 pare exam])le III with the following. 



Example XXIII. — Location: rectangular space formed by 

 water ])ipe, side of house and fence. Main sheet horizontal, 

 rectangular attached to fence, house and pipe. Gallery behind 

 the pipe. Guard web exceedingly low. Snares few. 



Occasionally webs are encountered in which the guard 

 sheet is present in some portions of the outer side while it is 

 absent from others. The following observation is an illustration 

 of this. 



Example XXIV.— Location : between stone wall and 

 wooden post. Main sheet attached in the angle between the 

 post and wall. The sheet is horizontal, bagging slightly in the 

 center. Gallery in crevice between wall and post. A low 

 guard web is present near each extremity of the exposed side of 

 the web while the guard web is absent from the middle of that 

 side. Snares iQ.\\', attached to both wall and post. 



Among inclined webs, the guard sheet is mure often pres 

 ent than it is in horizontal webs. But even here the number of 

 times the sheet is present predominates but little over the num- 

 ber of times that it is absent. Example IV, VI, XII and XX 

 are illustrations of cases wnere the guard sheet is absent, 

 although the web is inclined. 



As in horizontal webs, so here, the guard sheet is some- 



