74 MEANING OF ORDERS. 



cea, the front one being the largest ; and in the. 

 Insects there are three nervous centres, the larg- 

 est in the head, a smaller one in the chest, and 

 the smallest in the hind body. Now according 

 to this greater or less individualization of parts, 

 with the corresponding localization of the ner- 

 vous centres, naturalists have established the rel- 

 ative rank of these three groups, placing Centi- 

 pedes lowest, Spiders next, and Winged Insects 

 highest. But naturalists may, and indeed they 

 actually do, differ as to this estimation of the 

 anatomical structure, for the Spiders are placed 

 above Insects by some naturalists, and many even 

 consider them a distinct class. Have we, then, 

 any means of testing its truth to Nature ? Let us 

 look at the development of these animals, taking 

 the highest order as an illustration, that we may 

 have the whole succession of changes. 



All know the story of the Butterfly with its 

 three lives, as Caterpillar, Chrysalis, and Winged 

 Insect. I speak of its three lives, but we must 

 not forget that they make after all but one life, 

 and that the Caterpillar is as truly the same be- 

 ing with the future Butterfly, as the child is the 

 same being with the future man. The old signifi- 

 cance of the word metamorphosis the fabled 

 transformation of one individual into another, in 

 which so much of the imagination and poetical 

 culture of the ancients found expression still 



