xvi 



CONTENTS. 



PAGE 



satisfactory character. Information contained in books 

 which treat expressly of trees, e.g., Griipin's Forest Scenery : 

 equally unsatisfactory. Difficulties attaching to the in- 

 quiry from the circumstance that we nowhere see trees 

 presenting indications of natural old age, and that we see 

 everywhere trees of great age — as old, in fact, and as 

 large, as any of their kind have ever been known to reach — 

 still growing as vigorously as in their earliest years. Re- 

 markable statement in Isaiah Ixv. 22. 



LETTER III. 25 



Corporation-theory of trees resumed. Re-statement of this 

 theory. The theory itself only a part of a more general 

 theory in Vegetable Physiology. Statement of this general 

 theory. All plants, even those called perennial, really 

 annuals — some wholly disappearing by decomposition at the 

 end of the year they are evolved, — portions of others re- 

 maining for ulterior purposes in the vegetable economy of 

 nature, but still remaining only as dead organic matter. 

 AU plants evolved either from seeds or buds, or both. Buds 

 equivalent to seeds, and merely fixed or adherent seeds. 

 The produce of the buds of trees identical in character with 

 seedling tree-plants ; and trees themselves merely the pro- 

 duct of tree-plants issuing from buds and growing parasiti- 

 cally on the persistant dead remains of the tree-plants of 

 former years. Inferences : Is^, trees, as such, without 

 natural limit to their age or size ; 2ndly, tree-plants, how- 

 ever, live but one year, and attain to a comparatively small 

 size. 



LETTER IV. ...... 30 



Subject continued. The persistent dead remains of the tree- 

 plants of former years serve to the living and growing 

 plants of the current year the purposes of a permanent 

 mechanical support and of a temporary soil. Illustration 

 of these statements as regards the two great divisions of the 

 tree tribe. And, 1st, as regards the Exogen. Disposition 

 of the plants as successively developed year by year in the 

 vertical direction. Plan of fir tree. The bud at the sum- 

 mit of the first year's plant sends upwards a new shoot and 



