COMPOSITE SNARES AND SECTORAL ORBS. 



147 



on any of the adjoining islands, althongli tlicre appears no physical rea- 

 son why the species should not occur all along the seaboard. ^ 



The female is a beautiful, as well as large, spider. The body is over 

 an inch long and the longitudinal spread of the legs is nearly four inches. 

 The cephalothorax is jet black above, but covered, except in spots, with 

 silver colored hairs. The abdomen is not oval but cylindrical in shape, the 

 length nuicli greater than the width. In color it is olive brown, a light 

 yellow above, and variously marked with yellow and white spots and stripes. 

 The legs are yellow, with dull red annuli and feet. The first two and the 

 fourth pairs have at tlie tips of the femur and tibia strong hair brushes 

 or feathery tufts to which the best known species of the genus owes its 

 name— plumipes, featherfoot, or plumefoot. The male, like that of Argiope, 

 is very small in comparison witli his mate, who is four or five times larger 

 than he. He is not more than a quarter 

 of an inch long and is of uniform dull 

 brown color. 



Prof. Wilder found the spiders in for- 

 ests spinning their webs between trees and 

 shrubs, sometimes within reach, 



„ but oftener ten or fifteen feet 



Snare. 



or even more from the ground 

 where the sunlight could strike them. The 

 orb varies from one foot to three or four 

 feet in diameter, as large as a wagon wheel. 

 It is composed of two kinds of silk, of 

 which one is white or silver gray, inelas- 

 tic and perfectly dry. To this belong the 

 radii, foundation lines and rctitelarian supports. The spirals, on the con- 

 trary, are a bright yellow or golden hue and very elastic. This 

 o- , is a remarkable peculiarity, which I have never seen but once, 

 in an exceptional case of the web of the Furrow spider woven 

 in captivity. This had a bright, golden yellow color, which cDutinued 

 throughout several months, during which I preserved the web. I attribute 

 this phenomenal appearance to some abnormal condition of the spinning 

 organs, by which the glands that furnish the flossy, yellowish silk used 

 for blanketing the cocoon and for winter covering, had been required to 

 secrete material for snare weaving. P>ut with Nephila the yellow secretion 

 appears to be habitually used for the viscid s])irals. This color marks the 

 webs of the genus generally, as described l)y Vinson (of African spiders) 

 and others. 



The si)iral scaffolding, however, is spun of white silk, and is not re- 

 moved after tlie coni])lotion of the s])inds, an exception to the habit of 



Fig. 138. Section of the orb of Nephila. 

 (After Wilder.) 



^ I have had specimens from Florida. 



