6 Smith: Botanical Sui'Vl'v for Local Natimtlixts' Societies. 



therefore an opportune time to consider the difficulty and to 

 propose some way to its solution. 



There are two distinct points of view in reg-arding- the plant- 

 life of a district. The existing- literature on plant-life embodies 

 the past work of botanists and local societies ; it regards plants 

 almost entirely from the floristic point of view. The botanical 

 survey, on the other hand, considers the vegetation of an area. 

 The floristic method of study has as its first object the prepara- 

 tion of lists of species found in a certain area — parish, county, 

 or country — and the recording of their relative frequency or 

 rarity ; the species in the lists are arranged under genera, 

 natural orders, etc., the whole constitutes the flora. The next 

 step is to consider the distribution of the species and genera 

 over the earth, to find where they occur, where absent, and to 

 compare one flora with another. Other questions of floristic 

 interest are the origin and migration of species, the present 

 conditions of existence, and the history of development. The 

 botanical characters of most importance in the study of flora 

 are those of the race, particularly the floral organs. In York- 

 shire we have a Flora for each of the Ridings, and several local 

 Floras. These are indispensable aids in the method now advo- 

 cated, they form a most valuable basis for further work, and we 

 are extremely fortunate in possessing them. 



In considering the vegetation, the first step is to find out 

 what plants grow together under similar climatic conditions 

 and soil (edaphic) conditions, and to ascertain the essential 

 characters which adapt the plants of such a community to 

 their particular environment. Thus a peat bog, a dry heath, 

 and a limestone scar each represent an area of uniform environ- 

 ment ; the list of species covering any one of these, includes 

 plants belonging to widely diff'erent genera and natural orders, 

 they have no kinship in the floristic sense, but they are related 

 in that all are adapted to live together under certain conditions, 

 the essential characters being found mainly in the leaves, stems, 

 roots, and other vegetative organs. The species found in a 

 particular environment constitutes a plant-association, and, by 

 arranging them in the order of their frequency, a picture of the 

 vegetation of the selected area is conveyed to the botanist. By 

 placing together the various plant-associations one may repro- 

 duce the whole vegetation of a parish, a. river-basin, or a country. 

 It is then possible to compare the distribution of vegetation 

 with climate, soil, and otiier factors of environment. The study 

 of \egetation thus becomes a study of plant-associations. 



Naturalist, 



