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controlling. To understand the vegetation of a region one must ascertain not only what are its physical, meteorological and geological features, but much more what sorts of plants control its water, meadow, plain, or forest vegetation. Directed towards the latter ends, statistics have a very different meaning. Such work is the aim of the new geographical botany. "When we hear of a district," say Schroeter and Stebler, "that it is covered with extended fields of turf-rush or of bromegrass, that tells us more of the nature of the region than long lists of meteorological data. It also tells us more than the mere occurrence of the species in question of itself"

A notable contribution to this department of the science is Dr. Drude's new work, "Deutschlands Pflanzengeographie," of which the first part appeared in January last. The sub title of the work gives a clue to its purpose. It is stated to be "ein geographisches Charakterbild der Flora von Deutschland." Much has been done in recent years towards such characterization of restricted districts, or for large areas as regards certain kinds of vegetation. But Dr. Drude in giving a complete picture of the vegetation of as large a country as Germany has, in one sense, made an epoch in geographical botany. Such a work demonstrates that the era of preparation is passed. A mere cursory examination of the work serves to convince the reader that the theory and system of plantgeography have been thoroughly worked out, and that henceforth workers will be busied chiefly with their application to other regions rather than with devising new methods.

As has been remarked, in order to be of value, statistics must be based not upon the systematic groups of plants but upon groups founded on biological considerations, so far as they indicate a positive role in the vegetation of the region in question. Such groups are called vegetation-groups. Dr. Drude points out also that the proportions of the number of representatives of the several orders, genera, or other systematic groups are not to be reckoned with the whole flora of a region as represented by a certain number of species, but with the biological plant-community of the region. Accordingly he constructs some thirty-five vegetation-groups for the flora of

Germany. The thoroughness of this may be judged from the fact that he begins with trees and ends with plankton-algæ.

Germany belongs to the Middle-European region which, bounded by the Pyrenees, the Alps, and the Balkan system, stretches along the northwest border of the Russian steppes to the arctic flora which extends over the north of Europe. The region includes also the wooded portions of the Scandinavian countries. Throughout this large region, as regards the distribution of families and genera, the same fundamental character prevails. Carrying the principles of division further, and observing on the one hand lesser influences of climate and physiognomy and on the other the division of the floral-elements into "Genossenschaften," subdivisions, or "Vegetationsregionen" are made. Germany and the neighboring regions of the Alps and Carpathians fall into five such divisions; the region of the north-Atlantic lowlands, the region of the southBaltic lowlands and uplands, the region of the middle and south German highlands and lower mountain districts, the region of the higher mountain districts and subalpine formations, and the region of the higher mountain formations of the Alps and Carpathians. The region of central France and the west-Pontic region, to which belong the southwestern and southeastern neighbors of Germany respectively, include also isolated spots in Germany itself. Dr. Drude's maps show that the first two regions are continuous in extent. The first includes Holland and North Germany west of the Elbe and the western portion of the Danish peninsula, the second EastPrussia and Pomerania, being bounded roughly by the Oder on the west. Between the Elbe and the Oder is a neutral zone, transitional between the two regions. The whole of middle and south Germany to the Alps constitutes the third region. But along the northern borders of the Alps and here and there throughout south Germany, as for instance the Harz forest, the Thuringian forest, the Black forest, in isolated spots, we find the fourth region, the region of subalpine forests. Along the upper Rhine here and there are localities belonging to the region of central France, and in the southeastern portion are many localities belonging to the west-Pontic region.

But geographical botany today does not stop with the distribution of the wild flora. Cultivated plants, native useful plants, weeds, and the flora of waste places come in for their share of consideration and are treated in turn. The plants whose seeds are mixed with those of cultivated plants and are thus sowed and grown involuntarily are placed in the group of cultivated plants. But a more important group is formed by the species introduced and supported incidentally by the cultivation and occupation of the soil by man. A notable instance of this is a group of "saltpetre plants" due to the use of nitrate fertilizers.

It would become tedious to enumerate the many striking features of the work and the ideas which they suggest. The work is in some sort a summary of geographical botany as it now stands. So much material necessarily takes on a new aspect when brought together and digested, though we have been more or less acquainted with a large part of it in its scattered condition. As part of a whole, each fact seems something new. We may safely predict that a great impetus will be given to this kind of botanical work in regions remote from Germany by Dr. Drude's book, since it presents a practical outline which will not fail to be taken advantage of. Our own country furnishes many excellent opportunities which the various biological and botanical surveys now in progress are already beginning to seize. The example of such a geographico-botanical survey of a large country, on a large scale, will be a great inspiration.

Dr. Drude's book is most interesting reading, and as a compendium of the latest results in a growing and important department, as well as in its more immediate purpose, is of the highest value.

EDITOR'S TABLE.

THE bestiarians are still actively engaged in endeavoring to prevent humanitarians from prosecuting their good work of relieving human disease and suffering. Their latest move is to endeavor to get national legislation to suppress physiologic research by vivisection in the Dis

trict of Columbia. There are various reasons why humanitarians should take especial pains to prevent this attempt to restrict human knowledge and prevent the dimunition of human suffering. They suppose that National legislation once secured, State legislation will be easily obtained. Perhaps they expect to get a national law forbidding such research in all parts of the United States! Such people must, however, present very clean hands in the cause of prevention of cruelty to animals before they appear as advocates of the suppression of the most important method known of reducing human suffering. Do any of them wear articles made from the furs of animals? Do they carry pocket-books or grip-sacks made of the skins of animals? Do they permit animals to be plucked of feathers for their comfort or ornament? Finally, do they encourage the enormous slaughter of animals by land and sea, for food and other purposes?

There is much important work done in the departments at Washington which will be affected by the bill that is soon likely to come before the Senate, and the educational institutions of the highest grade will be injured by it if it passes.

The bill it is said will be favorably reported to the Senate. It will, however, probably not come up for final action before the next session. Meanwhile biologists and humanitarians generally should urge on their Senators and Representatives the importance of defeating the bill in the interest of progress and humanity. Let them write to their Representatives for the Public Documents on Antivivisection of the District Committee of the Senate. The Medical men are active, but the biologists are not yet sufficiently awake to the importance of the situation. If members of the National legislature are fully informed, they will hardly pass the bill.

RECENT LITERATURE.

The Cambridge Natural History.'-Sometime ago we referred to the volume of this series containing the Molluscs and Brachiopods; the second volume in order of publication is now before us. As in the former volume there is a great lack of uniformity in the different parts

1 The Cambridge Natural History, Vol. V. Peripatus by Adam Sedgwick; Myriapods by F. G. Sinclair; Insects, Part I by David Sharp. London, Macmillan and Co., 1895, pp. xi-584.

which compose it, a lack, in part attributable to the individuality of the authors, in part to an apparent failure on the part of the editors to lay down guiding rules for their authors.

Mr. Sedgwick devotes 26 pages to Peripatus, giving a good general account of the group, in its structure, development and habits, and following it with a list of the known species, essentially the same as that in his previous monograph. From his familiarity with the group no

one was better able to treat of the group than he.

Mr. Sinclair should have been almost equally familiar with the Myriapods for he has published both on the structure and the embryology of the group, and yet his account is much less satisfactory. The general account of the habits is good and is based to a large extent upon the author's own observations, but we wish he had put into English some of the facts ascertained by vom Rath. The classification adopted, that of Koch, is rather antiquated (1847) while the investigations of Grassi, to say nothing of the later researches of Schmidt and Kenyon, show that the Scolopendrellidæ and Pauropidæ are not to be set aside as distinct from the Diplopoda, and the elevation of Cermatia to ordinal rank has very little in its support. One or two typographical errors are annoying. Scudder's figures of fossil Myriapods are attributed to "Meek and Worth," the author persisting in depriving the American paleontologist of the last syllable of his name. Here may be mentioned one of the inequalities of the work. While in treating of Peripatus a diagnosis is given of all (?) known species, in the Myriapods only the families are thus treated. Concluding the account is a discussion of the relationships of the group, and in this we find mixed up myths from Pliny and facts from other authors, including (p. 78) a quotation showing that the people of Rhytium were driven from their quarters by Myriapods, a statement which also occurs (p. 30) in another place. But in this whole part we see nothing but a feeble groping, not the firmness of the master hand. The chapter as a whole shows the lack of editorial supervision; its prolixity on minor points should have been suppressed.

The best of the book is that by Mr. Sharp-accounts of the Aptera, Orthoptera, Neuroptera and the lower Hymnoptera, the author using these names in the widest sense. In the introductory sections, dealing with the anatomy and embryology of the Hexapods, the author is evidently less at his ease that in the more systematic portion. Here he has given us one of the best of all books upon insects. The strictly systematic portion is well done, while the account of habits and transformation is excellent, and the perspective good. Thus the Mallophaga

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