FACT AND THEORY 237 



divisions, called classes, one of which is distin- 

 guished by bearing its seeds in inclosed packages 

 called ovaries ; the other bearing seeds which are 

 exposed or naked. The first of these classes 

 includes the vast majority of seed-bearing 

 plants; the other including principally those 

 trees, like the pine and the cypress, which bear 

 their seeds in open cones. 



Next on our chart we shall find that the class 

 is subdivided into orders. The order represents- 

 a collection of related families. As an example, 

 the order Eosales is made up of the rose family, 

 the bean family, the cassia family, the mimosa 

 family, and twelve other families closely allied. 



Below the order comes the family a division 

 which is still broadly inclusive; the rose family 

 for example taking in not only the rose itself, 

 but the apple, the blackberry, and sixty-two 

 other plants whose close relationship might not 

 at first be evident. 



From the family we next narrow down to the 

 genus which separates the rose from the apple 

 and the blackberry and gives each its own classi- 

 fication. 



Beneath the genus comes the species. 



And beneath the species the variety. 



We may take it as a safe observation that 

 the simpler the form of life, the less the 



