The rano-e of our native species should, however, be studied in relation to that of the range on the Continent. The countries in which British species are found on the Continent or elsewhere are cited by Hooker in his various works, in the Index Kewefists and Supplements, and Nyman's Sylloge; and the various floras of each country give a more accurate idea of the range of each species. A comprehensive work upon the geographical distribution of plants remains to be written.

Perhaps the thorniest side of botany is that of nomenclature. Until a student is quite proficient, however, this side-branch of botany should be left severely alone. Even specialists in this department of botany differ widely in their choice of names and the mode of citing them. There does not exist a single textbook upon the subject at the present time, and the history and data of nomenclature are scattered through a vast number of separate works, periodicals, and papers, to which access is not always easily obtained. The amount of bibliographical work to be done in this branch of botany is enough to occupy the entire attention of a student, a fact which no doubt causes many an exponent of the subject to dogmatize where little or no practical acquaintance with the plant itself has been obtained. Hence it is not to be wondered at that the field botanist and the pure nomenclaturist are often at variance.

Some principles affecting the nomenclature of plants have been given in Vol. I. At the present time specific names date from 1753, the date of Linnaeus's Species Plantarum, and the rules of nomenclature follow the Vienna Actes, or International Rules, adopted in 1905 (see Vol. I).

In so far as British plants are concerned, the nomenclature used in the standard works, such as Hooker's Students' Flora, Babington's Manual, or F. N. Williams's Prodromus Florae Britannicce, may suffice for the ordinary student. The history of the standard names or their synonyms, and dates of adoption, are given in the last, and some of the older works. The current names are given in Druce's List of British Plants, the London Catalogue of British Plants, and Rendle and Britten's List of Seed Plants.

Some useful papers upon nomenclature, touching the priority of names so far as a number of genera and species are concerned, have been written from time to time (e.g. Mr. G. E. Druce's papers On the Nomenclature of British Plants (1906-07)).

Further information will be found in the fournal of Botany, which is, in fact, largely concerned with nomenclature, and in the Reports of the Botanical Exchange Club of the British Isles and of the Watson Exchange Club.

So far as classification goes, changes are less frequent. Names may change often, but the order of arrangement of plants is less frequently altered.

For a good summary of this question in general, see Dr. A. B. Rendle's The Classification of Flowering Plants. Lindley's Vegetable Kingdom gives some details of the early classification. Sachs' History of Botany, Dr. J. R. Green's History of Botany, Mrs. Arber's British Herbals (Cambridge University Press), and Dr. Oliver's work in the same series all give details of famous botanists and their work, with some notes on classification. The classification used on the Continent is that of Engler and Prantl, which is summarized in Dr. Carter's Genera of British Plants, and followed in the Cambridge British Flora (Vol. II only published) by Dr. Moss. (See also a review of this and works by other Continental botanists by the same writer as they affect the British Flora.) Warming's Systematic Botany is a general textbook of some value, with an appendix or summary of different systems by Dr. Ainsworth Davis.

The system followed in this country so far is that of Bentham and Hooker in Genera Plantarum.

In order to go into the question both of nomenclature and classification, upon which only hints can be given here without any discussion of either subject, the student must not confine his attention, however, only to British works, but must study foreign works, a selection of which only can be given. (Vide Bibliography.) The subject is so vast and difficult that it can only be referred to in this work. Fuller bibliographies are given in the works cited. Though not up-to-date as far as authorities and information go, two small works that may be useful, as giving the meaning of scientific names and a certain number of synonyms for species, are Names and Synonyms of British Plants by J. Egerton-Warburton, 1889, and Botanical Names for Englisli Readers by R. H. Alcock, 1876.

Indispensable is Index Kewensis by B. D. Jackson, and Durand's Supplement. A handy pamphlet is index Abcedarins by W. P. Hiern. Also useful are Pritzel's /cones Plantarum, Nyman's Conspectus, and De Candolle's Prodroimis, as well as Just's Botanischcr Jahresbericht.

In conclusion, it must ever be borne in mind that identification and correct naming, though the first essential steps towards the investigation of a plant, are nothing more. They constitute the indispensable means to a nobler end. namely, the inexhaustible study of the structure and activities of the organism, but can never be an end in themselves.