HUTCHINSON'S POPULAR BOTANY 



confess that our faith in the philosopher's opinion, no less than in the 

 virtue of the poet's recipe, is somewhat weak. Observation teaches that 

 Life which distinguishes the Mineral from the Vegetable and Animal 

 Kingdoms, does not spring up spontaneously. The .principle of Life must 

 be there first, under whatever conditions; and hence 

 that the doctrine of " T ^ f T ' 1>ffi " or 



Life from Life,' 



it is safe to affirm 

 or biogenesis, is the true doctrine. 

 " Dead matter," said Lord Kelvin 

 before the British Association 

 some years ago, " cannot become 

 living matter without coming 

 under the influence of matter 

 previously alive. This seems to 

 me as sure a teaching of science 

 as the law of gravitation. I am 



(NT^Ifl ready to adapt as an article of 



AflHi^BnH scientific faith, true through all 



space and through all time, that 

 Life proceeds from Life and 

 nothing but Life." 



The German botanist Schlei- 

 den, taking the crystal as the 

 type of the most perfect form 

 of inorganic body, thus beauti- 

 fully contrasts it with a living 

 organism, the Barley-plant (see 

 fig. 12). "The crystal does not 

 spring at once a perfect Minerva 

 from the hand of Jupiter; the 

 matter of which it is formed 

 undergoes a constant series of 

 changes, the final result of which 

 is the completed shape of the 

 crystal. The crystal, too, has an 

 individual history, a biography, 

 but only a history of its becoming, 

 its origination. . . . Plants and 

 animals form the most distinct 

 contrasts to this, and herein lies 



that common nature, which induces us to comprehend them in one concep- 

 tion, as organic or living existence. ... In spring we commit the barley- 

 corn to its nurse, the earth ; the germ begins to move, starts from its 

 envelopes, which fall to decay. One leaf after another appears and unfolds 

 itself; then the flowers display themselves in a thickly crowded spike. 

 Called forth through wonderful metamorphoses, in each originates the germ 



FIG. 13. A BOGUS PLANT THE 



LEAF INSECT. 

 An example of protective resemblance to vegetable forms. 



