1 50 ORGANS OF REPRODUCTION. 



phanic acid). Red colouring matters are procured from the root of 

 Anchusa tinctoria (alkanet), from Pterocarpus santalinus, Dracaena 

 Draco (Dragon's-blood), the root of Eubia tinctorum or madder (aliza- 

 rine), the root of Morinda citrifolia (Sooranjee), Haematoxylon campe- 

 chianum (logwood), Csesalpinia braziliana (Brazil wood), from Cam- 

 wood, also from Carthamus tinctorius (Carthamine), and from some 

 Lichens, as Roccella tinctoria (Archil and Litmus). Blue colouring 

 matters are furnished by the flowers and fruits of many plants, and 

 from the leaves of some, by chemical action. Indigo, a most valuable 

 dye, is procured by fermentation from various species of Indigofera, as 

 Indigofera tinctoria, Anil, coerulea and argentea, as well as from 

 Wrightia tinctoria, Marsdenia tinctoria, Nerium tinctorium, and Gym- 

 nema tingens, &c. The plants in full flower are cut and put into A-ats 

 with water, fermentation takes place, and a peculiar substance is formed, 

 which, by absorption of oxygen, becomes blue. The best and the 

 largest quantity of Indigo is produced in the Delta of the Ganges. 

 Several Lichens yield nitrogenous colouring matters, which give blue 

 and purple colours with alkalies, &c. Lecanora tartarea yields Cud- 

 bear. 



SECTION III. ORGANS OF REPRODUCTION. 



STRUCTURE, ARRANGEMENT, AND FUNCTIONS. 



323. The reproductive organs consist of the flower and its appen- 

 dages, the essential parts being the stamens and pistil. When the 

 flower, or at least the essential organs, are conspicuous, the plants are 

 called Phanerogamous (tfetvi^o;, conspicuous, and ya^o?, union or mar- 

 riage), or Flowering plants ; when they are inconspicuous, the plants 

 are Gryptogamous (K^TTTOS, concealed, and y^o?, union or marriage), 

 or Flowerless plants. The former include Exogens and Endogens, the 

 latter Acrogens and Cellular plants. On careful examination, it will be 

 found that the organs of reproduction and nutrition are modifications 

 of each other. The parts of the flower, as regards their development, 

 structure, and arrangement, may all be referred to the leaf as a type. 

 They commence like leaves in cellular projections, in which fibre-vas- 

 cular tissue is ultimately formed; they are arranged in a more or less 

 spiral manner, and they are often partially or entirely converted into 

 leaves. 



1. INFLORESCENCE, OR THE ARRANGEMENT OF THE FLOWERS ON THE AXIS. 



324. The arrangement of the flowers on the axis, or the ramification 

 of the floral axis, is called Inflorescence or Anthotaods (oivdos, a flower, 

 and T |/f, order). Flower-buds, like leaf-buds, are produced in the axil 



