been physically disconnected by the ocean for several geological ages, certainly since the Cretaceous period?* Dr. Guppy closes his paper by asking the question, "Whence came the Angiosperms which appear with the Upper Cretaceous period with such startling suddenness?" Down throughout the Mesozoic ages, the flora of the world was (as far as our knowledge extends) restricted to Conifers, Cycads, Ferns, and Equisetums-a gloomy and flowerless vegetation. Hitherto no examples of dicotyledonous plants had appeared, but with the Upper Cretaceous period a change in the flora took place so remarkable that Prof. Oswald Herr characterises it as "a new fundamental conception " introduced into the Vegetable Kingdom. It reminds one of the change which took place over Western Europe in architecture when the light and graceful "Early English" style replaced the massive and heavy "Anglo-Norman." To this change we are indebted for our forest trees, the oak, the walnut, the willow, the poplar, the plane, the hornbean, the liriodendron, the fig, magnolia, the myrtle, and the eucalyptus. Later on in early Tertiary times, fruit trees and flowering plants established their range, supplying us with food and decorating our hills and valleys. As the period for man's abode on earth approached, nature, under a guiding Providence, furnished and decorated his dwelling place. To the question above stated, Dr. Guppy gives no reply. It is so far an unsolved problem, which the geologist would try to answer by stating that the gap in time between the Lower and Upper Cretaceous was so immense that by a process of evolution the change resulted; but a botanist of eminence, Mr. Seaward, in his address to the British Association, states, "We are profoundly ignorant of the means by which nature produced this new creation." The reply which refers all such facts to "the imperfection of the geological record," has been characterised by an eminent man of science as "the inflated cushion on which you. try to bolster up the defects of your hypothesis." Not a bad illustration! Dr. R. P. COLLES.-In reply to your very courteous request * In the Animal Kingdom the development of the horse both in America and Europasia gives us an example of the process of nature above referred to. + Brit. Assoc. Report, 1903, f. 847. that I should send you, in writing, the remarks I made after the reading of Mr. Guppy's paper on Plant-Distribution, I can only repeat my answer that they are not worth it, except, perhaps, as relating to the Chairman's opinion that the author had not giver sufficient importance to human agency as one of the means employed in the distribution of plants. Many years ago I was for some time at Landawur, in the Himalayas, where there is a military sanatorium about 7,000 feet above sea-level. The steep sides of the mountain were wooded, principally with evergreen oak, the branches of which were thickly fringed with ferns; there were also rhododendrons growing as high as elms, with dark red flowers. Here and there, on the lower slopes, were small pine woods of wonderful beauty, and, I may also add, full of leeches, with which one's feet became covered when climbing up or down the steep khud (precipice) on which they grew. There were single dahlias growing wild on the mountain side in the places where there were no trees, forming patches of brilliant colourscarlet, sulphur, and white. It was supposed that they were indigenous to the soil, and people wondered at this, as the extremes of climate in the Himalayas and the want of moisture for many months would be against the growth of such a plant. But our innocent speculations were one day ruthlessly overturned by someone saying, that in a little graveyard on the side of the hill above us, one of the graves had, some time ago, been planted with dahlias and that they had spread freely, partly from seed and partly from the clearing out of rubbish and superfluous clay, probably containing fragments of dahlia roots which were thrown down the hillside from the graveyard. In this case human agency would account for the appearance of this flower, but it would be interesting to learn if it still exists in the same latitude, or if it has gradually died out, as it might well have done after the lapse of years since I saw it there in 1872. Colonel T. H. HENDLEY, C.I.E. (CHAIRMAN).-Is enough stress laid upon the importance of human agency in the distribution of plants or in the changes in climate which affect it? For example is not the dessication of large tracts of country due, in some cases,. to neglect to maintain canals and other irrigation work, as has been the case in Mesopotamia; or to somewhat similar causes, as in the Western parts of the Punjab and Rajputana; or in others to diminution of the population from war or famine which has thrown land out of cultivation, as in Palestine. Was not the decay of prosperous regions, owing to a change of climate, caused by wasteful destruction of forest, as well as those already cited, and has not land planted with vegetation, especially trees, led to increased rainfall and the introduction of new plants? Is not this the case in Egypt? As to the dispersal, how are we to account for such cases as the appearance in India of large specimens of the Adansaria digitata, which is an important member of a genus confined to Africa and Australia (as Mr. Guppy says)? I have seen this magnificent tree, at one time thought to be the oldest tree in the world, in the ruins of Mandra, the famous capital on the Narbuda of the Sultans of Malwa, and it is found in other parts of India. Some believe it was introduced by the Portuguese only 300 years ago; others put back its introduction to a much earlier date. In any case, is not too much importance attributed to time in these questions? If the Portuguese theory regarding the introduction of the Baobab into Western India is accepted, only 300 years are required for a wide dispersal. Of other cases we have more accurate knowledge. Most of the European garden vegetables now in use in India, we learn on the authority of the Physician Bernier, were first introduced into the country a few centuries ago. The Emperor Baber has told us that before his time there was little fruit in the country, and it is certain that tobacco was unknown before the Moghul period, because the Emperor Jehangir, like so many other great Sovereigns of the time, threatened its use with death. Instances such as these might be multiplied indefinitely, I think, in proof of the view that human agency is of immense importance in plant distribution. Mr. MARTIN L. ROUSE.-The theory of the author of this learned paper is that every order or tribe was at the first created over a large proportion of the Earth's surface, and that, by the accidents of climate, exposure to wind or sun, elevation and character of soil, each split up into manifold genera and species more and more remote from one another over the vast region once covered by the original order or tribe. This agrees with the view of Linnæus, himself-whose reverent spirit none can impugn-for he thought that "Omnipotence created the orders, climate shaped these into genera, while the accidents" aforesaid "discriminated the genera into species." Doctor Guppy establishes his theory by the following arguments: - 1st. That the genus or sub-genus which contains more than any other the characters of an order, and appears thus to be the parent of its other genera, is the very one which is most widely distributed (of which phenomenon he, however, only actually cites two examples). 2nd. That among 23 orders and sub-orders that have been examined we get a result in a descending scale such as the theory would lead us to expect—namely that 92 per cent. of the tribes, 11 per cent. of the genera, and only 1 per cent. of the species are common to the Old World and the New. 3rd. That since the conditions under which land plants live differ far more amongst themselves than those under which fresh-water plants exist, we should expect to find far more species of land orders than of fresh-water ones; and, as a fact, we find ten times as many of the former as of the latter. 4th. That where the agencies of dispersal (currents, winds, and birds) have their fullest play in maintaining original species, there the number of strange species found is smallest. The case is very strong against the common theory of dispersal of genera from single centres, which other arguments of the author show to be untenable; but he does not overthrow the view that every genus, and perhaps every species, was originated in one or more of its present abodes. If the species and genera of each order are the result of differentiation, we should expect to see them forming hybrids between themselves; whereas even the species will not do this naturally-and to bring it about artificially is no easy task-all the proper stamens of the fruiting flower having first to be cut away, for if any of its own pollen be at hand its stigma will receive and assimilate this by preference and yield a flower lik itself.* In an article written a year ago from Palestine to the Gardeners' Chroniclet by our fellow-member Mr. Arthur Sutton, he described the abundance and beauty of two plants that grow side by side in many parts of Palestine-the Anemone coronaria and the Ranunculus Asiaticus. The form of the flowers is, he says, the same, * Chambers's Encyclopædia, Hybrids. and the prevailing colour of both is a deep red or scarlet; but the Anemone, like all its genus, is without a calyx, while the Ranunculus, of course, possesses one; and whereas the lovely shades of colour in the Anemone, varying from a pure white to deep mauve, found in comparatively few districts, are never seen in the Ranunculus, the rare tints of bronzy yellow, sometimes seen in the Ranunculus are never displayed in the Anemone--the plant that has no calyx never exchanging tints with the plant that has one. Again, the plant without a calyx always begins to bloom two or three weeks before the other. So there is no hybrid between Anemone and Ranunculus. And yet they have bloomed in company for ages and in all positions and climates of Palestine--on the low plain of Sharon near the sea, by the Lake of Galilee, 700 feet below sea-level (where tropical plants thrive), and on the slopes of Mount Carmel, 1,500 feet above sea-level (where hail and snow are frequent); which fact, as Mr. Sutton points out, ought, on the theory of evolution, to have wrought some lasting change of form in both plants: but there has been neither hybridizing nor differentiating whatever. Similarly, the few plants that have been found in Egyptian mummy coffins are identical with their present-day representatives; and in the parallel case of animals Mr. Sutton cites a work published by Messrs. Lortet and Gaillard, of Lyons, entitled La Faune Momifiée de l'Ancienne Egypte, which "shows clearly that the species embalmed 20, 30, or even 70 centuries ago have not changed in the least." * Two instances alone are insufficient to support the author's first argument; one would like to know how many more he has in reserve. And as regards his third argument, since the surface of actual land is far greater than that of lakes, rivers, and streams, and has been so ever since the creation of man, and since fresh-water plants can grow only along their borders or in their slower currents, we should expect to find a smaller variety of fresh-water plants than of land-plants in the world; and, as a fact, we have a smaller number of families and genera as well as of species of the former. A cordial vote of thanks to the Author was then put from the Chair, and carried unanimously; the meeting then adjourned. * Perhaps these may be found in his volume referred to by the Secretary. |