INTRODUCTION. 25 



The destructive powers of these creatures, so insignificant in 

 appearance, are still more surprising. During the spring of a 

 single year they can effect the ruin of a house by destroying the 

 beams and planks. The town of La Rochelle, to which the 

 Termites were imported by an American ship, is menaced with 

 being eventually suspended on catacombs, like the town of 

 Valencia in New Grenada. It is well known what destruction is 

 caused when a swarm of Locusts alight in a cultivated field, 

 and it is certain that even their larvse do as much injury as 

 the perfect insect. All this sufficiently proves the destructive 

 capabilities of these little animals, which we are accustomed to 

 despise. 



M. Plateau has studied the power of traction in some insects, 

 the power of pushing in the digging insects, and the lifting 

 power of others during flight. He has thus been able to make 

 some most interesting comparisons, of some of which we will relate 

 the results. 



The average weight of man being 142 Ibs., and his power of 

 traction, according to Regnier, being 124 Ibs., the proportion of the 

 weight he can draw to the weight of his body is only as 87 to 100. 

 With the horse the proportion is not more than 67 to 100 ; a horse 

 1,350 Ibs. in weight only drawing about 900 Ibs. The horse, 

 therefore, can draw little more than half his own weight, and a man 

 cannot draw the weight of his own body. 



This is a very poor result, if compared with the strength of the 

 cockchafer. This insect, in fact, possesses a power of traction 

 equal to more than fourteen times its own weight. If you 

 amuse yourself with the children's game of making a cockchafer 

 draw small cargoes of stones, you will be surprised at the great 

 weight which this insignificant looking animal is able to accomplish. 



To test the power of traction in insects, M. Plateau attached 

 them to a weight by means of a thread fastened to one of their feet. 

 The Coleoptera * are the best adapted for these experiments. 



The following are some of the results obtained by the Belgian 

 physician : Carabus auratus can draw seven times the weight of 

 its body ; Nebria brevicollis, twenty-five times ; Necropkorus ves- 

 pillo, fifteen times ; Trichius fasciatus, forty-one times ; and 



* For explanation of the words Coleoptera, &c., see p. 28. ED. 



