194 HOW TO STUDY PLANTS. [LESSON 32. 



blance. For instance, having first become acquainted with the 

 Convolvulus family in the genus Calystegia (556), we recognize it 

 at once in the common Morning-Glory, and in the Cypress- Vine, 

 and even in the Dodder, although these belong to as many different 

 genera. Having examined the common Mallow (552), we immedi- 

 ately recognize the Mallow family (Malvaceae} in the Marsh-Mallow, 

 sparingly naturalized along the coast (Manual, p. 66), in the Glade 

 Mallow and the Indian Mallow (p. 67), in the Hibiscus or Rose- 

 Mallow (p. 68), and so of the rest; because their relationship is 

 exhibited in their general appearance, and in the whole structure of 

 the flowers, if not of the foliage also. 



566. So the study of one plant leads naturally and easily to the 

 knowledge of the whole order or family of plants it belongs to ; 

 which is a great advantage, and a vast saving of labor. For, 

 although we have one hundred and thirty-four orders of Flowering 

 Plants represented, in our Botany of the Northern States, by about 

 2,350 species, yet half of these species belong to nine or ten of these 

 orders ; and more than four fifths of the species belong to forty of 

 the orders. One or two hundred species, therefore, well examined, 

 might give a good general idea of our whole botany. And stu- 

 dents who will patiently and thoroughly study out twenty or thirty 

 well-chosen examples, will afterwards experience little difficulty in 

 determining any of our Flowering Plants and Ferns, and will find 

 the pleasure of the pursuit largely to increase with their increasing 

 knowledge. 



567. And the interest will be greatly enhanced as the student, 

 rising to higher and wider views, begins to discern the System of 

 Botany, or, in other words, comprehends more and more of the Plan 

 of the Creator in the Vegetable Kingdom. 



