196 CONSERVATIVE ORGANS. [LECT. V. 



nerally at the base ; but roots originate from that 

 part also of the stem which is above ground. Thus 

 the Strawberry throws out lateral shoots, which 

 are termed wires, from which roots descend at in- 

 tervals into the ground ; and from the stems of 

 the Ivy, the Jasmine, the Ash-leaved Trumpet- 

 flower, Bignonia radicans, and other plants which 

 fix themselves to walls and rocks, roots are pro- 

 truded,, serving equally to imbibe nourishment 

 and to give support to those climbing plants. 

 Whenever a stem is surrounded with earth, roots 

 are protruded from it. Du Hamel filled a cask 

 with earth, and boring holes through the bottom 

 of it, supported it on stakes three feet from the 

 ground. He then pushed slips of plants through 

 the earth in the barrel, and planted their ends, 

 which passed out at the holes in the bottom of the 

 cask, in the ground below it. These ends took 

 root ; the parts between the ground and the cask 

 put forth branches and leaves ; those surrounded by 

 the earth in the cask protruded roots ; and those, 

 again, above it became clothed with foliage. It 

 is, also, well known that, if a twig of a Willow be 

 bent and each end of it stuck into the ground, 

 roots will be protruded from both extremities, 

 whilst the middle or arched portion will be covered 

 with leaves and branches ; and the extremities of 

 the branches of all ligneous plants throw out roots, 



