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semblance in essential characters. Some of these orders are well-defined natural groups whose affinities are undoubted, like the great families of Compositæ and Cruciferæ; others are more or less artificial, and appear to pass into each other by almost insensible gradations; their limits are variously defined by different botanists, and are often made dependent upon obscure structural peculiarities only appreciable by an advanced student of the science. The Flora of this country is too limited to require reference to the minute and complex details of botanical classification, upon which the general arrangement of the Vegetable Kingdom has been founded; and the characters given in the accompanying Table of Orders and Genera must be regarded as applicable only to British plants,—it being intended merely as a Key or Index to enable the reader to refer any wild plant to the Natural Order under which it is figured and described in this work. The British Flowering Plants are here arranged in the order stated below,—with few exceptions, that usually adopted by British botanists.
EXOGENS.
Thalamifloræ.
1. Ranunculaceæ.
2. Berberidaceæ.
3. Nymphæaceæ.
4. Papaveraceæ.
5. Fumariaceæ.
6. Cruciferæ.
7. Resedaceæ.
8. Cistaceæ.
9. Violaceæ.
10. Droseraceæ.
11. Polygalaceæ.
12. Frankeniaceæ.
13. Caryophyllaceæ.
14. Linaceæ.
15. Malvaceæ.
16. Tiliaceæ.
17. Hypericaceæ.
18. Aceraceæ.
19. Geraniaceæ.
20. Balsaminaceæ.
21. Oxalidaceæ.
22. Staphyleaceæ.
Calycifloræ.
23. Celastraceæ.
24. Rhamnaceæ.
25. Leguminosæ.
26. Rosaceæ.
27. Onagraceæ.
28. Haloragaceæ.
29. Lythraceæ.
30. Tamaricaceæ.
31. Cucurbitaceæ.
32. Portulaceæ.
33. Illecebraceæ.
34. Crassulaceæ.
35. Grossulariaceæ.
36. Saxifragaceæ.
37. Umbelliferæ.
38. Araliaceæ.
39. Cornaceæ.
40. Loranthaceæ.
41. Caprifoliaceæ.
42. Rubiaceæ.
43. Valerianaceæ.
44. Dipsaceæ.
45. Compositæ.
46. Campanulaceæ.
47. Lobeliaceæ.
48. Vacciniaceæ.
