178 



HISTORY OF THE VEGETABLE KINGDOM 



wliicli belong to Monadelphia, are said to be 

 triandrous, tetrandrous, pentandrous, or poly- 

 androus, according as tliey contain three, four, 

 five, ten, or a greater number of stamina united 

 by their filaments into a single body. In Dia- 

 delphia and Pofyadelphia, the same method is 

 followed, the orders having the names of the 

 first classes of the system. 



Si/ngenesia, the nineteenth class of the sexual 

 system, is one of the most extensive. In fact, 

 the synantherea; or syngenesian plants form 

 about the twelfth part of all the knowTi vegeta- 

 bles. It was therefore neccssaiy to divide this 

 class into several orders, to facilitate the inves- 

 tigation of its different species. Linnoeus, ac- 

 cordingly, instituted six orders. But here the 

 number of the stamina could not be employed 

 ns the basis of these subdivisions, it being almost 

 invariably five; for which reason he derived the 

 characters of the orders from the structure of 

 the little flowers which constitute the assem- 

 blages known by the name of compound flowers; 

 for in consequence of constant abortions, there 

 occur along with the hermaphrodite flowers, 

 male flowcre, female flowers, and even sometimes 

 perfectly neutral flowers. Linnseus, whose poeti- 

 cal fancy is observable in all the names wliich 

 he imposed upon the different classes and orders 

 of his system, looked upon these associations 

 and mixtures of flowers as a kind of polygamy/. 

 This name he accordingly gave to each of the 

 six orders of syngenesia, adding to it a distinc- 

 tive epithet. The following are their characters. 



Order 1 . Polygamia mqualis. All the flowers 

 are hermaphrodite, and in consequence are all 

 equally fertile; as in thistles and goatsbeards. 



Order 1. Poli/gamia superflua. The flowers 

 of the disk are hermaphrodite, tliose of the cir- 

 cumference female; but both kinds fui-nish per- 

 fect seeds, as in wormwood and tansy. 



Order 3. Polygamia frustranea. The flowers 

 of the disk are hermaphrodite and fertile, those 

 of the circumference neutral or female, but 

 sterile in consequence of their stigma, and tliere- 

 fore entirely useless; whereas in the preceding 

 order they were only superfluous, as the knap- 

 weeds and sunflowers. • 



Order 4. Polygamia necessaria. The flowers 

 of the disk are hennaphrodite, but sterile, in 

 consequence of an imperfect formation of the 

 stigma; those of the circumference are female, 

 and fecundated by the pollen of the former. 

 In this case, they are therefore necessary for tlie 

 preservation of the species : the marigold is an 

 example. 



Order 5. Polygamia s-gregata. All the flowers 

 are hermaphrodite, and placed close together, 

 but are separately contained each in a small 

 involucre of its own, as in the genus Echinops. 



Order C. Polygamia mmogamia. The flowers 

 arc ail hermaphrodite, but they are simple, and 



are separated from each other, as in the violet, 

 lobelia, balsamine. 



The last order, as may easily be seen, has no 

 affinity to the rest, possessing nothing in common 

 with them but the union of the stamina by 

 their anthers. 



In Gynandria, the twenty-firet class of the 

 sexual system, there are four orders which are 

 derived from the number of the stamina. Thus 

 we have Gynandria monandria, as in the genera 

 Orchis and Oplirys; Gynandria diandria, as in 

 Cypripedium ; Gynandria hexandria,as in Aris- 

 tolochia; Gyandria polyandria, as in Arum, 



Monmcia anHDiaicia present in some measure 

 a union of all the modifications which we have 

 remarked in the other classes. Thus Monoscia 

 contains monandrous, triandrous, decandrous, 

 polyandrous, monadelphous, and gynandrous 

 plants. Each of these vaiieties is used for the 

 establishment of a distinct order in this class. 



Picecia contains a still greater number of 

 varieties, the characters of which being the same 

 as those of some of the classes previously es- 

 tablished, are employed as designative of the 

 orders. 



The twenty-tliird class, Polygamia, which 

 contains plants with hermaphrodite flowers and 

 unisexual flowers intermingled, whether on the 

 same individual, or on two or three distinct in- 

 dividuals, has, in accordance with these circum- 

 stances, been divided into three orders. 



1. Monoscia, in which the same individual 

 bears monoclinous flowers, and declinous flowers; 



2. Pioscia, in which there are hermaphrodite 

 flowers on one individual and unisexual flowers 

 on the other; 3. Triaecia, in which the species 

 is composed of tliree individuals, one bearing 

 hermaphrodite flowers, another male flowers, 

 and the third female flowers. 



Cryptogamia, the twenty-fourth and last class, 

 is divided into four orders : 1, Ferns; 2. Mosses; 



3. AJgte; 4. Fungi. 



TABLE OF 



CLASSES. 

 1. MONANDRIA. 

 Plants f)f one 



CLASSIFICATION. 



ORDKRS. 

 ( 1 Monogyiiia 



stainooandoneor 

 two pistils. 



2. DIANDRIA. 



Tlie British 

 plants in this 

 class hare two 

 Btampns and one 

 or two pistila 

 the flowers are larger and 

 their parts more oistinct 

 than in thn tirst rlasa. 

 3. TUIANDRIA. 



Plants of tliree 

 stamens, and one, 

 two, or throe pis- 

 tils. Besides a 

 considerable nnmhpr of 

 vi'ry beautiful plants, and 

 a few useful in medicine, 

 this class contains the 

 most important natural 

 family in the whole rirrle 

 of vegetation— the Graini- 

 nea. 



in) 



L2 Digynia ^^ 



' 1 Monogynia 



- 2 Digynia 



1 MonogynJa 



2 Dtgynia 

 ,3 Trigynia 



Nf 



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