SYSTEMATIC BOTANY. 



in number and position, the seeds are differently 

 disposed, being contained in a more evident 

 capsule than the preceding. To this order the 

 bignonia, antirrhinum, mimulus, gloxinia, common 

 foxglove (Digitalis purpurea), c. belong. 



XV. TETRADYNAMIA. Flowers with six sta- 

 mens, four of which are longer than the other two. 

 Linnaeus divided this class into two orders SlLl- 

 CULOS.E and SlLlQUOSiE the former being a 

 short roundish pod (c\ and the latter a long one 

 (a). The cabbage, turnip, radish, wallflower, 

 stock, rocket, &c. belong to this class. This is a 

 truly natural class of plants, forming the order 

 Crucifera of Jussieu ; great similarity of the 

 flowers, seeds, &c. being observable throughout 

 the whole of the genera. The calyx is four-leaved, 



a I e 



Stamens and Seed-vessels. 



sepals concave, equal, and deciduous ; corolla of 

 four petals, claws inserted into the receptacle, 

 limbs widening outwards in a cruciform manner. 



XVI. MONAD ELPHIA. The stamens are united 

 into one set or brotherhood in this class, which is 

 divided into eight orders, founded on the number 



Octandria. Heptandria. Pentandria. Triandria. 



of the stamens, not on that of the pistils, as in 

 other classes. In the first order, TRIANDRIA, we 

 find several beautiful Cape bulbs as the Tigridia, 

 Herbertia, &c. Of the second order, PENTAN- 

 DRIA, the passion-flower is the most remarkable. 

 There is also the Erodium or stork's-bill, a genus 

 allied to the geraniums. The third order, HEX- 

 ANDRIA, contains but one genus, a bulbous-rooted 

 plant, called Gilliesia graminea, having grass-like 

 leaves and curious flowers. The fourth order, HEP- 

 TANDRIA, contains the pelargoniums, commonly 

 called geraniums. The fifth order, OCTANDRIA, 

 having eight stamens, united in one set, contains 

 the genus Aitonia, named by Linnaeus in honour 

 of the late William Aiton, royal gardener at Kew. 

 In the sixth order, DECANDRIA, we find the true 

 geraniums or crane's-bills. The seventh order, 

 DODECANDRIA, are all tropical plants. In the 



Polyandria. Dodecandria. Decandria. 



eighth order, POLYANDRIA, are Althea, Lavatera, 



Hibiscus, Sida, silk-cotton tree, the tea-tree, and 

 its magnificent congener, the camellia. 



XVII. DIADELPHIA. Flowers having two sets 

 or brotherhoods of stamens. In general, nine are 



Hexandria. 



Pentandria. 



united together, with a single one by itself, which 

 is accounted the second brotherhood. Examples : 

 Monnina trifolia; Fumaria, fumitory ; and Poly- 



Decandria. 



Octandria. 



gala, the milkwort, and many leguminous plants 

 such as the common pea, furze, broom, genista, 

 laburnum, rest-harrow, and lupine. 



XVIII. POLYADELPHIA. This class contains 

 all plants whose flowers have their stamens ar- 

 ranged in many brotherhoods. Among the plants 

 of this class is the Theobroma, which yields 



Polyandria. 



Decandria. 



chocolate. This disposition of the parts on which 

 the order is founded, is exemplified in the species 

 of Hypericum or St John's wort. 



XIX. SYNGENESIA. This large class contains 

 all the compound or composite flowers which form 

 the natural order Composite. The first order is 

 yEQUALiS, in which all. the florets are hermaphro- 

 dite. It contains the sow-thistle, lettuce, hawk- 

 weed, burdock, artichoke, &c. The second order 



Superflua. 



/liqualis. 



is SUPERFLUA, the flowers of which have the 

 florets of the disc bisexual, and those forming the 

 rays female. This is also a very large order, of 

 which tansy, chamomile, helichrysiums, xeran- 

 themums, dahlias, &c. are examples. The third 

 order is FRUSTRANEA, so called because i 

 florets of the disc are bisexual, and those in the 

 ray or margin neuter. To this belongs the sun- 

 flower, the Rudbeckia, Coreopsis, &c. The fourth 



