118 A JOURNEY IN BRAZIL. 



his cocoon on the leaf. -We watched him for a long time 

 with the lens as he wove his filmy tent. He had 

 arched the threads upwards in the centre, so as to leave a 

 little hollow space into which he could withdraw ; this tiny 

 vault seemed to be completed at the moment we saw him, 

 and he was drawing threads forward and fastening them at 

 a short distance beyond, thus lashing his house to the leaf 

 as it were. The exquisite accuracy of the work was 

 amazing. He was spinning the thread with his mouth, 

 and with every new stitch he turned his body backward, 

 attached his thread to the same spot, then drew it forward 

 and fastened it exactly on a line with the last, with a 

 precision and rapidity that machinery could hardly imitate. 

 It is a curious question how far this perfection of workman- 

 ship in many of the lower animals is simply identical with 

 their organization, and therefore to be considered a function, 

 as inevitable in its action as digestion or respiration, rather 

 than an instinct. In this case the body of the little animal 

 was his measure : it was amazing to see him lay down his 

 threads with such accuracy, till one remembered that he 

 could not make them longer or shorter ; for, starting from 

 the centre of his house, and stretching his body its full 

 length, they must always reach the same point. The same 

 is true of the so-called mathematics of the bee. The bees 

 stand as close as they can together in their hive for 

 economy of space, and each one deposits his wax around 

 him, his own form and size being the mould for the 

 cells, the regularity of which when completed excites so 

 much wonder and admiration. The mathematical secret 

 of the bee is to be found in his structure, not in his 

 instinct. But in the industrial work of some of the 

 lower animals, the ant for instance, there is a power of 



