Page:The Journal of Indian Botany.djvu/151

Rh evolution, if the State cared to engage 100 trained observers to collect, observe and measure, and 10 trained systematists to examine and collate results for five years, facts would emerge at the end which would establish, at any rate for the time being, the limits of species and lower units and their developmental tendencies. The writer is not for a moment advocating such a course of action as a practical way of spending the State finances! The illustration is merely given by way of showing that so long as the evidence is completely available no problem is absolutely beyond solution. In short, where we find in the floras so-called "critical species" their critical character is duo to human infirmity, and is not absolute.

Generally speaking all Indian workers seem to find that where the Flora of British India gives many varieties a mixture of species may be suspected, which patient collecting and collection of material will (and as a fact often does) clear up. Conversely it must be admitted that some species in the Floras can be broken down by patient collection of transitional series. Those two facts would go a long way towards establishing the truth of the proposition enunciated in the preceding paragraph. But unfortunately, partly owing to post-Linnasan and especially modern Mendelian researches into the origin of species, and partly owing to the extremely minute examination to which certain particular genera have been subjected in the West, and the recognition thereby of numerous intra-specific forms, there has been of late years a strong tendency to cast scorn upon Systematics, and even to take the final step of asserting that the individual is the only ultimate unit. Fortunately, however, both the economist who obtains products from plants and the field-worker who observes and collects them, know that the individual is only the unit in the same sense that no two members of one nation or even of one household are exactly alike, and that just as human beings can be and must be grouped into larger units on various scientific and social basses, so among plants there are units containing millions—often countless millions—of individuals, whose common characters can and must be described, and to which the application of a "barbarous binomial" is both convenient and necessary.

The unit commonly accepted and used for more that a century and a half is the Linnaean species. And it is this particular unit upon which soma students of genetics to-day seem to cast such scorn, regarding it as an erroneous conception and no true phenomenon. Now this view is one which the writer believes to be wrong. The practical field-worker knows that in a region with which he is familiar he can at once assign to their Linnaean species all but au