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Overview

Huntsman Spiders

The Wolf Spider

The Voracious Water Spider

Orb Web Builders

A Fascinating Sight

Riddle of the St. Andrew's Cross

The Tailed Spider

The Amazing Stick Spider

The Death's Head Spider

Queen of Spinners

The Hairy Imperial Spider

The Beautiful Spiny-Bellied Spider

The Crab Spider

The Jumping Spider

The Flying Spider

Bird-Catching Spiders

A Spider that Barks?

Trap-Door Spiders

The Brown Trap-Door Spider

The Funnel-Web Spider

The Venomous Red-Back Spider

Deadliest of Creatures

       

 

Riddle of the St. Andrew's Cross

The webs of the St. Andrew's Cross spiders (Argiope aetheria and pieta) are of considerable interest and seldom fail to attract attention because of the de­corative saltire of fluffy white silk super-imposed upon its meshes. Argiope aetheria, the commonest species, is a striking creature with the abdomen adorned with bands of yellow and chest­nut-brown, while the forepart of the body (cephalothorax) is densely clothed with long, recumbent silvery hairs. The purpose of the silken adornment of the snare is obscure, and several theories have been advanced to explain it. It is suggested that it strengthens the web—but other web-spinners construct quite efficient snares without such rein­forcement. That . it provides camouflage for the spider as it rests in the centre of the snare with its legs, lying in pairs along the arms of the cross, has also been suggested. The snowy-white cross, however, seems to attract rather than to distract attention from the occupant.

Since the spider usually rests behind the cross, it is possible that it may serve to divert the aim of a hungry bird which may attempt to snatch the spider from its resting place. The whole question is further complicated by the fact that the cross is not infrequently .wanting, ap­parently at the whim of the individual spider, without any detriment to either web or occupant. The whole question would surely reward detailed study.

 

 

 

 

 

 

   
Wonder Book of Knowledge