288 PROFESSOR BABINGTON ON RUBUS IN 1891. we call them species or varieties, or only forms ; for who can define a species now that we have had to give up the old views that all species were intended to be permanently distinct ? Now that we know how extensively slightly varying forms are reproducible from seed, we must either accept each of these forms as an aboriginal species, or give up the theory that those first created have been kept specifically distinct until the present time. We who have been trained to hold this latter view find it difficult to give up. But the search after truth leads us necessarily to accept the former view. Although therefore I have called many species forms in this essay, I must not be supposed to state or believe that their characters do not vary to a greater or less extent under changed circumstances of climate or locality. We find that very similar plants gathered in the north or west are often only very similar, although we give them the same names. For this reason, when we gather a plant in Devon or Cornwall, we look to M. Genevier's elaborate book for its name, when working in the east or north-east of England and Scotland our attention is necessarily directed to the valuable descriptions of Dr. Focke, or the Scandinavian botanists ; and even then we must not always expect the plants to be absolutely identical. In accepting nomenclature, I quite agree with Dr. Focke that we are not obliged to "waste our time in studying the foolish writings of every ignorant and mischievous manufacturer of names " (Journ. Bot. 1890, 98). I may quote another remark of the same author which seems to be very applicable to what is being attempted in botanical nomen- clature. He says: "We have far too many botanical rag-collectors, who, in following out their view of priority, penetrate everywhere, dragging matters again into the light of day which had better have been left in the shades of night" (Focke, Syn, p. 58). It is a matter of mere convenience what plan of nomenclature we follow. Calling plants species or subspecies makes very little difference, for we have to define the plants just as much on one plan as on the other. If we are to advance our knowledge and ascertain the extent of variation of each form (and that is, I conceive, our duty as students), we may fairly say with Lindley {Synopsis, ed. 1, ix.) that "our daily experience shows that excessive analysis is far preferable to excessive synthesis." As has been remarked, it is quite apparent that there are very many more forms of plants that are continued by seed than we have been accustomed to believe ; and that we must give up the favourite idea that those are distinct species which are easily and fully reproducible by seed. We must also give up the once prevalent view that a single marked character may always be depended upon as the mark of a species. After much study we learn how difficult it is to define almost any one of the recognised species, so as to include all its possible forms, and so as to separate it clearly from all possible forms of allied plants. In this book I do not pretend to have entered into that difficult subject with the elaborate detail which has been so well carried out by Dr. Focke ; but I have done so rather more than is usual with other rubologists. Neither have I attempted to form an analytical i
