ISO ANALYTICAL TABLES. 



as an expeditious method of botanical analysis. They are the result of much labor 

 and investigation, since each character employed required a previous examination 

 of all the species included under it. The process of analysis by these tables consists 

 of a simple series oi dilemmas or alternatives ; the decision being, in almost all cases, 

 to be made merely between two opposite or obviously distinct characters. These 

 decisions or (A7c/« was being, moreover, few in number, conduct the student with 

 absolute precision (provide'^cl the tables be free from error, and the specimen a good 

 one) to the order or genus to which his plant belongs, by once or a few times reading 

 across the page. The advantages thus afforded will be duly appreciated, at least by 

 those who have hitherto been subjected to the drudgery of reading through whole 

 pages of dry generic descriptions, and that too, often, without arriving at any satis- 

 factory conclusion. 



In regard to the generic characters employed in the tables, it will be observed that 

 they are drawn from leaves, fruit, flower, Or any portion of the plant which suited 

 our convenience, — our only inquiry being after those which appear to us the most 

 obvioics and constant. It should be remarked, however, that in many instances 

 these characters are not strictly applicable to all the known species belonging to 

 those particular orders or genera, but only to those which are described in this work ; 

 that is, found in the United States, north"of lat. 381". In our choice of terms we have 

 always, of necessity, studied the utmost brevity of expression, but have used none 

 but such as are explained in the glossary or in the body of the work. 



Although the manner in which these tables are to be used will in general be ob- 

 vious at a glance, yet it may not be unprofitable to attend to the following directions 

 and illustrations. 'We will suppose the student to be in possession of an unknown 

 plant which he wishes to study by the aid of the Flora, in other words to analyze. 

 To this end, he first determines to which of the six great classes of the natural sys- 

 tem it belongs, — either by his previous knowledge of their characters, which should 

 be thoroughly understood, or by an appeal to the first synoptical view, page 130. 

 Thus he inquires, — 



1. Is the plant a flowering or flowerless one ? Ans. Flowering. It belongs there- 

 fore to Phjenognmia. Turn next to the 'id couplet. 



2. Are the leaves net-veined, &c. or paraEel-veined, &c. Ans. Net-veined, and 

 the flowers are not wliolly trimerous ; that is, the petals, sepals, and stamens, are in 

 in threes, but the carpels are single. The plant belongs, therefore, to Exogens. 

 Turn to the 3d couplet. 



3. Stigmas present, &c. or stigmas 0, &c. Ans. Stigmas present. The_ plant 

 therefore belongs to Class I. Angiospermous Exogeus. Next ascertain to which of 

 the sub-classes it belongs, by synopsis 2d. 



4. Are the petals distinct," or united, or 0, &c. ? Ans. Distinct. The plant will 

 be found therefore among the Polypetalous Exogens. Now turn to the Conspectus 

 of the Orders of this subdivision, and inquire, — 



7. Is the plant an herb or a shrub ? Ans. A shrub. Turn then to couplet 54. 

 54. Leaves opposite, or leaves alternate ? Ans. Alternate. Ti;rn to 65. 



65. Stipules present, or stipules none ? Ans. Stipules none. 70. 



70. Flowers cf ?, or § ? Ans. §. Turn then to couplet 72. 



72. Stamens (00) indefinite, or 6, or 4, or 5 ? Ans. 6 ; and the plant belongs there- 

 fore to the natural order Berberidacece. The pupil now turns to Order vl. and 

 inquires in the Conspectus, — 



Is the plant an herb or a shrub ? Ans. A shrub, and therefore belongs to Berberis, 

 genus 1st. Turn finally to that genus, and study the species. 



Again, suppose the plant to be an herb. Turn to couplet 8. 



8. Leaves alternate, &c. or opposite ? Aiis. All radical. 9. 



9. Stipules present or ? ^4?j,'!. Present (radical). 34. 



34. Flowers regular or irregular ? Ans. Regular. 35. 



35. Stamens monadelphous or distinct ? Ans. Distinct, and the order sought is 

 Rosace*. Then turn to Order XLVIII. and inquire, — 



Ovaries free or adherent ? A)is. Free. 



Naked or enclosed, &c. ? Ans. Naked. 



Are they 3 — 50 in number or 1 only ? A7is. 3 — 50. 



Are they in fruit follicles, a compound berry, or achenia ? Ans. Achenia. 



On a dry receptacle or juicy ? Atis. Dry. 



Caudate with the persistent style or not ? A?is. Not caudate. 



Leaves simple or compound ? A7is. Compound. 



Is the plant caulescent or acaulescent ? A7is. Acaulescent, and the genus is 

 Waldsteiuia. Turn lastly to that genus, and learn the species. Further illustrations 

 are perhaps unnecessary. 



