EXTERNAL CONFIGURATION OP PLANTS. 195 



definite conclusions on some of the questions sug- 

 gested, the considerations brought forward in this 

 paper may be of service in calling attention to the 

 importance of certain branches of natural history. 

 The geographical distribution of species, their verti- 

 cal range, their habitats and dimensions, have not 

 hitherto received the attention they deserve. The 

 subject is full of interest, but at every stej) the 

 necessity for further observations has been apparent. 

 New lines of investigation seem to open up on 

 every side. We have here and there caught glimpses 

 of the great principles by which Nature fashions 

 her strange and manifold productions. But the 

 external morphology, the internal anatomy, and 

 minute structure of a living body, will be invested 

 with a new and fascinating interest when we are 

 able to connect each organ with its peculiar function, 

 and when we can trace to its origin every morpho- 

 logical feature which it presents. 



