420 FOOD OF INSECTS^ 



nice perception, that M. Q, D'Isjonval, to whom Trt* 

 are indebted for the fact, has proposed them as most 

 accurate barometers. He asserts that if the weather be 

 about to be variable, wet and stormy, the main threads 

 which support tlie net Avill be certainly short; but if 

 fine settled weather be on the point of commencing^, 

 these threads will be as invariably very long ^. Without 

 going the length with M. D'Isjonval of deeming his dis- 

 coveries important enough to regulate the march of 

 armies, or the sailing of fleets, or of proposing that the 

 first appearance of these barometrical spiders in spring 

 should be announced by the sound of trumpet, I have 

 reason to suppose from my own observations that his 

 statements are in the main accurate, and that a very 

 good idea of the weather may be formed from attending 

 to these insects. 



The spiders which form geometrical nets differ from 

 the weavers also with respect to the situation in whicii 

 they watch for their prey. They do not conceal them- 

 selves under their net, but are placed in the centre 

 v.ith their head downwards, and retire to a little apart- 

 ment formed on one side under some leaf of a plant, only 

 when obliged by danger or the state of the weather. 

 The moment an untbrtunate fiy or other insect touclics 

 the net, the spider rushes towards it, seizes it with her 

 fangs, and if it be a small species at once carries it to 

 her little cell, and, having tliere at leisure sucked its 

 juices, throws out the carcase. If the insect be larger 

 and struggle to escape, with surprising address she en- 

 velops it with threads in various directions, until bot]» 

 its wings and legs being effectually fastened, she carries 



* Brez, La Flore dcs InsectophilcSy 129. 



