THE BANDED EPEIRA 177 



get them caught in the sticky matter. Does the Epeira 

 know the secret of fatty substances? Let us try. 



I rub my exploring straw with slightly oiled paper. 

 When applied to the spiral thread of the web, it now no 

 longer sticks to it. The principle is discovered. I pull 

 out the leg of a live Epeira. Brought just as it is into 

 contact with the lime-threads, it does not stick to them 

 any more than to the neutral cords, whether spokes or 

 part of the framework. We were entitled to expect this, 

 judging by the Spider's general immunity. 



But here is something that wholly alters the result. I 

 put the leg to soak for a quarter of an hour in disulphide 

 of carbon, the best solvent of fatty matters. I wash it 

 carefully with a brush dipped in the same fluid. When 

 this washing is finished, the leg sticks to the snaring- 

 thread quite easily and adheres to it just as well as any- 

 thing else would, the unoiled straw, for instance. 



Did I guess aright when I judged that it was a fatty 

 substance that preserved the Epeira from the snares of 

 her sticky Catherine-wheel? The action of the carbon- 

 di sulphide seems to say yes. Besides, there is no reason 

 why a substance of this kind, which plays so frequent a 

 part in animal economy, should not coat the Spider very 

 slightly by the mere act of perspiration. We used to 

 rub our fingers with a little oil before handling the twigs 

 in which the Goldfinch was to be caught; even so the 

 Epeira varnishes herself with a special sweat, to operate 

 on any part of her web without fear of the lime-threads. 



However, an unduly protracted stay on the sticky 

 threads would have its drawbacks. In the long run, 



