174 ACADEMIC BOTANY. 



422. Natural Analysis, as compared with Artificial, — which is given 

 in Lesson XXXVI. ,— is not so readily mastered. The Artificial Method 

 exacts only that the plant shall come within the requirements of its 

 24 Classes and their simple Orders ; the characters of these are so few 

 and so easy to find out that no trouhle can be had in discovering them. 

 But the student, after filling his herbarium with representatives 

 of each, will have no knowledge of their natural relations. Let us 

 take the Olive (Fig. 71) and Sage (Fig. 187) by way of illustration. 

 Both belong to the Series Phanerogamia. It is simple enough to 

 classify these two plants by the Artificial System : The flower in each 

 has 2 stamens, 1 style ; both, then, belong to the Class Diandria, 

 Order Monogynia (441, 443). We see at a glance, however, that they 

 are very distantly related. Eemembering what Linnseus himself said 

 about studious inquiry into nature's inethpds, let us follow the lead of 

 Jussieu and apply his rules (31) as we proceed to analyze and classify 

 the same plants according to the Natural Method : 



Riore I. The OJive and Sage have visible flowers producing seeds 

 containing an embryo with differentiated organs; they belong, there- 

 fore, to the Series Phanerogamia. They have an ovary ; they there- 

 fore belong to the Class Angiospermje. They have an embryo with 2 

 cotyledons; they therefore belong to the Sub-Class Dicotyledonse, or 

 Exogens. 



Rule IT. "We next examine the petals. They cohere into a tube at 

 base ; the plants are therefore in the same Division Monopetalaa. 



Rule III. Next the Stamens. In both plants the stamens are epi- 

 petalous (253, on the corolla) ; the corolla is free, which makes the 

 stamens- free also. Both plants are therefore in the same Subdivision 

 Ovary Free. But from this point the plants diverge widely ; nature 

 has separated them. So we "weigh" their distinctive characters 

 separately. Beginning with the Olive, we apply the remaining 

 Eules : 



Rule IV. The Olive seed has abundant perisperm ; 



Rule V. The Eadicle superior ; 



Rule VI. The corolla valvate in aestivation ; 



Rule VII. The calyx regular, 4-toothed ; the corolla regular, 4- 

 parted ; the stamens 2, inserted on the corolla-tube and alternate 

 with its divisions ; the style simple ; the ovary free, 2-celled, the cells' 

 2-ovuled, the ovules pendulous, anatropous. The fruit is a drupe, 

 2-seeded, or 1-seeded by abortion. 



We examine the stem ; the wood is hard and tough. The leaves ; 

 they are opposite, entire, coriaceous. The plant is a tree 20 to 25 feet 

 high, of bushy habit. We find a small number of plants resembling 

 the Olive; among them the Jasmin, Fringe-tree, Lilac, and Ash; 

 these are accordingly grouped around the Olive, and form the Order 

 Oleacece. 



423. We next examine the Sage in the same way (Fig. 187) : 

 Rule IV. Seed without perisperm ; 



Rule V. Eadicle inferior ; 



Rule VI. Calyx irregular, bilabiate, lips 2-fid and 3-fld. Corolla 

 ditto, lips in reverse order to those of the calyx; stamens 2, inserted 

 on the corolla-tube, anthers dimidiate ; ovary free, 4-celled, cells nearly 

 separate, making the ovary appear 4-lobed ; cells each 1-ovuled ; 

 ovules erect, anatropous ; style simple, basal, or gynobasic ; stigma 



