Superfamily Argiopoidea 



free zone. Across the centre of the web there is stretched a 

 stabilimentum. 



The stabilimentum of Cyclosa differs greatly from that of 

 a garden spider. It often consists largely of the remains of the 

 insects that the spider has destroyed fastened together and in place 

 with threads of silk. Frequently a cast skin of the spider is woven 

 in with the insect remains; and bits of vegetation, as fallen bud- 

 scales, are utilized. The stabilimentum in a web that was built 

 near a place where rugs were frequently beaten consisted largely 

 of lint; evidently the spider had removed all of the fibres that had 

 lodged in its web and used them in making its stabilimentum. 

 Sometimes the stabilimentum consists entirely of silk. 



There is no retreat, the spider remaining constantly on the 

 web . It rests on the hub in the centre of the stabilimentum, and 

 appears like a part of the rubbish fastened in it. 



Emerton states that the egg-sacs are fastened into the 

 stabilimentum in the middle of the summer. 



Cyclosa caroli (C. car'o-li). — The characteristic feature of 

 this species is the very long and slender abdomen. The adult 

 female measures from one fourth to one third inch in length. 



This spider is remarkable for its self protective habits. These 

 I observed in the jungle near Miami, Fla. The orb of the 

 adult is about six inches in diameter. The female fastens her 

 egg-sacs in a series which extends across the orb from the hub 

 to the upper margin like a stabilimentum, and looks like a dead 

 twig caught in the web. This band of egg-sacs and the spider are 

 of the same gray colour. When disturbed the spider rushes to 

 the band and appears as if it were a part of it. And here it will 

 cling motionless even when the band is removed from the web. 

 A spider which 1 removed with its egg-sac and placed in a bottle 

 was still in this position on the band ten minutes later. 



I also observed smaller individuals shake their webs; these 

 clung to the stabilimentum, projecting the body at right angle 

 to it, and in this position shook the web violently. The evident 

 object was to frighten away the intruder. 



The young, when they emerge from the egg-sac, are not tailed. 



This is a southern species which has been found as far north 

 as the District of Columbia. 



Cyclosa bifurca (C. bi-fur'ca). — The strange form of the 

 abdomen sharply distinguishes this species from the other species 



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