SPIDERS' WEBS 



95 



for the construction of the cocoon. Each sort of 

 silk is made by a collection of glands that open near 

 the end of the body by a little spout called the spin- 

 neret. The lines of a geometrical web are laid 

 down in the following way. First an outline is 

 drawn ; to form this the female shoots out the 

 requisite thread, fastens it to some support, carries 

 it in her hind feet, streaming out of the spinneret and 



Fig. 20. — Web and Nest of Agelena, spread on grass. — ('Riverside 

 Natural History,'' by permission of Messrs. Houghton, Mifflin eV Co. , 

 Boston, U.S.A.) 



hardening as it emerges. Presently it touches a twig 

 or leaf, to which the spider fastens it and stretches it 

 tight with her claws. Then, letting herself straight 

 down and drawing out the silk behind her, she forms 

 one of the vertical sides. Afterwards the other sides arc- 

 completed in the same fashion. Across this framework 

 the spider draws a thread, fastens it with her claws, 

 and tightens it, so as to form the diagonals. From the 

 centre of this she travels to another point of the 



