112 



AMERICAN SPIDERS AND THEIR SPINNING WORK. 



FIG 



ium dif- 

 ferens. 



clings to her web by one long fore leg, while with other legs she revolves 

 her cocoon, using the hind legs, as is customary, to draw out the spinning 

 stuff. This issues in numerous diverging filaments, which bunch up in 



minute loops as the abdomen 

 descends, and are beaten down 

 smooth by the spinnerets. 



Our widely distributed Latro- 

 dectus mactans 1 quite resembles 

 Tepidariorum in cocooning habit ; 

 but its ovoid cocoons are larger, 

 being a full half inch at the longer 

 axis, and somewhat more spheri- 



. 107. Cocoons of Theridium tepidariorum, hung in her ca | i n shape. She makes at least 

 snare. (About natural size.) 



as many as four or five cocoons. 

 Theridium serpentinum Hentz 2 is one of our common Lineweaving spi- 

 ders, whose snares are found in dimly lighted cellars and in rooms aban- 

 doned or rarely used. In the angle of a window or wall the 

 Therid- mother spreads her snare of intersecting lines, and establishes 

 herself at one end thereof, always well towards the top. In the 

 course of time she succeeds in thickening her dwelling place by 

 added threads, until it has formed a sort of shelter of lines much more 

 closely set than those of the rest of the snare. In the neighborhood of 

 this dwelling place and on 

 a line therewith, or just a 

 little above it and to one 

 side, she spins several co- 

 coons, in number four or 

 five usually, but sometimes 

 as many as eight, as shown 

 in the figure. (Fig. 108.) 

 They are little white, oblong 

 or flask shaped flossy balls, 

 about quarter of an inch in 

 diameter, in the centre of 

 which the eggs are depos- 

 ited. In the delicateness and 

 scantiness of the enveloping 

 tissue, this cocoon resembles 

 Steatoda borealis and Phol- 

 cus phalangioides. The eggs 

 are distinctly seen through the silken envelope. When the spiders are 

 hatched they hang for a little while in clusters like minute swarms of 



FIG. 108. Cocoons of Theridium serpentinum in site at top of 

 her snare. (Natural size.) 



1 Lathrodectus formidabilis Walck. See also Vol. I., page 274. 



2 I am not positive as to the identity of this species. 



