42 TALKS AFIELD. 



takes to know much of botany ; and the 

 classification itself is of interest to the logi- 

 cian, as affording the best illustration of in- 

 ductive and dichotomous arrangement. The 

 system of botanical classification is founded 

 upon the inductive principle of first learn- 

 ing the characters of individual plants, and 

 then seizing upon the most salient and per- 

 manent features by which many plants may 

 be associated together. Among the appar- 

 ent confusion of forms and of structures in 

 plants, it is not strange that the ordinary 

 observer fails to recognize any general points 

 of agreement. There evidently must be 

 more points of agreement than of difference 

 between two or more plants before we can 

 group them together. They must agree 

 with one another, but must differ from other 

 groups. The two great sub-kingdoms or 

 series of plants illustrate this proposition ; 

 the flowerless plants possess a common char- 

 acter of reproducing themselves by spores, 

 while the flowering plants agree in repro- 

 ducing themselves by means of seeds; be- 

 tween these two sub-kingdoms there is a great 

 external dissimilarity in this respect. These 

 characters of spore - bearing and of seed- 

 bearing are not readily recognized by those 



