196 SYSTEMATIC BOTANY. 



requisite is, its Natural Order, and the first step in 

 analysis is an examination of the several organs, one 

 by one, until the general structure is well understood. 

 This done, the experienced botanist, who has in mem- 

 ory the characters of all the Orders, might determine 

 at once to which of them the plant in question belongs. 

 But the beginner must be content with a longer course 

 of inquiry and comparison, a course which might be 

 indefinitely long and vague without the use of 



507. Analytical Tables. These are designed to 

 shorten and define to exactness the processes of anal- 

 ysis. Those which appear in the present work are 

 peculiar in form, and more copious and complete than 

 the tables of any other similar work. These tables, 

 with proper use in connection with the specimen, will 

 very rarely fail to conduct the inquirer almost imme- 

 diately to the right Order, Genus, and Species. 



We subjoin a few examples of the analysis of par- 

 ticular species by the aid of these tables. If the exer- 

 cise be conducted in the class-room, the successive 

 steps in the process (indicated by the numbers 1, 2, 3, 

 etc., below) may be assigned, in order, to each pupil 

 in the class. 



ANALYSIS OF A POLYPETALOTJS HERB. 



508. To determine the Cohort. A good specimen of a little yellow- 

 flowered herbaceous plant, common in the grassy fields of cool regions, is sup- 

 posed to be now in the hands of each pupil of the class. (1.) Tne first pupil, 

 reading (if necessary) the characteristic of each sub-kingdom, pronounces the 

 plant one of the Phaenogamia, and refers the next pupil to the Classes I., 



n., or m. 



(2.) The next reads the characters of those Classes, and comparing the 

 specimen (which has net-veined leaves and 5-merous flowers), concludes that it is 

 an Exogen. Refer next to the Class I. 



(3.) "Stigmas present. Seeds inclosed in vessels." 



" Stigmas none. Seeds naked. (Pines, Spruces, etc.) " Our plant has 

 stigmas, etc., and, moreover, is not a Pine, Spruce, etc. It is, therefore, an 

 Angiosperm. Refer next to Cohorts 1, 2, or 3. 



