96 



THE COMMON SPIDERS 



spider moves along. There is nothing adhesive about the web. 

 It serves merely as a clearing where insects may alight to rest 



and the spider may have a good 

 chance to run after them. Where 

 the web is made under plants or 

 rocks a great number of threads are 

 carried upward from it, which may 

 help in stopping insects (fig. 227), as 

 they do in the webs of Linyphia. 

 (See p. 135.) 



Tegenaria derhamii. — This is a com- 

 mon species in barns and cellars, 

 and has probably been imported from 

 Europe, where it is even more com- 

 mon. The head is high and wide, 

 as in T. mcdicinalis. The mandibles 

 are less swelled in front and the 

 eyes are closer together than in that 

 species, and cover more than half 

 the width of the head (fig. 229). The 

 cephalothorax is shorter and wider 

 across the hinder half and the abdo- 

 men shorter than in viedicinalis, and 

 the legs are longer and more hairy. 

 The colors are lighter and the hairs 

 of the whole body longer. The 

 female is two-fifths of an inch long. 

 The cephalothorax is pale, with two 

 gray stripes. The abdomen is marked 

 with a series of gray spots, formed of 

 a middle row more or less connected with two side rows ; the 

 front of the abdomen often pale, with the markings faint 

 (fig. 228). The legs are long, the first and fourth pairs nearly 



Figs. 228, 229. Tegenaria derha- 

 mii. — 228, female enlarged four 

 times. 229, front of head. 



