40 



MANUAL OF BOTANY 



appearance of trees. If the lower branches are the longest 

 and become shorter as they approach the top, the whole will 

 take the form of a cone or pyramid, as in the Spruce Fir ; if the 

 middle branches are longer than those of the base and apex, the 



Fig. 53. 



Fig. 55. 



Fig. 54 



Fvj. 53. A [joi-tion of the coDimon Strawbei'i'y plant, a'. M\ axis pToduciiipr 

 a tuftnf leaves at its extremity, the upper of which, ;■, are weU developed 

 and f.T«n, and the lower rudimentary. From the axil of one of the latter 

 a second axis or runner, a'\ arises, bearing arndimentary leaf, /', near the 

 middle, and a cluster of leaves, )■, at its end. a'". A third axis produced 



in a similar manner to the former. /, /. Roots or rootlets. Fig. 54. 



Offset of Sempervivum. Fig. 55. Plant showing the process of layering. 



general appearance will be rounded or oval, as in the Horse- 

 chestnut ; if those of the top are the most developed, the form 

 will be umbrella-like, as in the Italian Pine. 



In many of the trees with excurrent stems the lower branches 

 perish comparatively early, instead of growing out to great 



