II 
SPIDERS 
39 
cally, as is invariably the case with the genus Epeira : they were 
separated from each other by a space of about two feet, but 
were all attached to certain common lines, which were of great 
length, and extended to all parts of the community. In this 
manner the tops of some large bushes were encompassed by the 
united nets. Azara 1 has described a gregarious spider in 
Paraguay, which Walckenaer thinks must be a Theridion, but 
probably it is an Epeira, and perhaps even the same species with 
mine. I cannot, however, recollect seeing a central nest as 
large as a hat, in which, during autumn, when the spiders die, 
Azara says the eggs are deposited. As all the spiders which I 
saw were of the same size, they must have been nearly of the 
same age. This gregarious habit, in so typical a genus as 
Epeira, among insects, which are so bloodthirsty and solitary 
that even the two sexes attack each other, is a very singular fact. 
In a lofty valley of the Cordillera, near Mendoza, I found 
another spider with a singularly-formed web. Strong lines 
radiated in a vertical plane from a common centre, where 
the insect had its station ; but only two of the rays were 
connected by a symmetrical mesh-work ; so that the net, 
instead of being, as is generally the case, circular, consisted 
of a wedge-shaped segment. All the webs were similarly 
constructed. 
1 Azara’s Voyage, vol. i. p. 213. 
darwin’s papilio feronia. 1833, now called ageronia feronia, 1889. 
