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ing. The questions: what really takes place when an embryonic cell becomes a permanent cell; the reciprocal influences of separate plant organs, which we call correlation; further the problem of polarity; stand out with great clearness in the phenomena of regeneration. I can, how

us, and not with theoretical assumptions of new formations as the result of woundand far-reaching phylogenetic hypotheses. The theory of mutations formulated by de Vries with such brilliant results is the result of this kind of patient and step-bystep observation of the now living plant world. The observations of de Vries show us that specific characters arise not through the accumulation of useful variations, but by leaps, and have nothing at all to do with direct adaptation. Such as are disadvantageous in the struggle for existence are weeded out. But selection can not effect the origin of specific or organization characters as such, and this makes it clear to us why-from the human standpoint-one and the same problem may be solved in such different fashions.

The mutation theory of de Vries limits itself to that alone which the observation of the present moment can come at, to the origin of the so-called 'minor species.' But how the division of the plant kingdom into the larger groups has come about, how it has happened that the 'archetypes' have reached such marked development and others have died out or remained in abeyance, are further problems, the solution of which may not so soon be looked for. For this, however, the more intimate knowledge of the factors which regulate the develop ment of the individual from the egg cell to the ripening of the fruit, forms a fundamental starting point. For this purpose plants are especially suitable, since, on the one hand, because of the possession of a punctum vegetationis, they are in later life also provided with embryonal tissue, and, on the other hand, because in their form they are more exposed to the influence of the outside world than the majority of animals.

An especially important means in order to the causal study of development has the research into those phenomena proved itself, which we designate the regeneration

ever, at this moment only indicate the problems, and can not point out the steps which have been taken toward their solution. A wide vista spreads out before us. The more must we wonder that of the countless botanical papers which appear each year not more than perhaps a dozen are concerned with the problem of development.

Summing up this brief presentation, it should have been shown that morphology, which originally formed a part of taxonomy, then grew apart from it as an independent discipline. Only when it gives up this separate position will morphology take on new life, for such a position is warranted only historically and not in the facts.

The earlier morphologists would have said that morphology has as little to do with the physiology as with the anatomy of plants, which latter, at the time when systematic botany was in the ascendant, they reckoned also as physiology. For physiology was then everything which was not taxonomy. Nowadays it would be carrying coals to Newcastle to point out the significance of the cell doctrine for morphology. For the understanding of alternation of generations, of inheritance and other phenomena fundamentally important to morphology the doctrine of the cell has become of basic significance. same is true in a higher degree for the relation between morphology and physiology, for all other tasks of the descriptive natural sciences are, after all, only preliminary attempts at orientation, which at length lead

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to experimental questioning, to physiology. Indeed, one may say that morphology is that which is not yet understood physiologically. The separation of the different tasks of botany is not in the nature of things proper, but is only a preliminary means at first to orientate ourselves with reference to the maze of phenomena. The barriers between these tasks must then in the nature of the case fall with further progress. I do not wish to deny the value of phylogenetic investigation, but the results which it has brought forth resemble more the product of creative poetic imagination than that of exact study, i. e., study capable of proof. If the knowledge of the historical development of plant forms hovers before us as an ideal, we shall approach it only when we attack the old problems of morphology, not simply with the old method, that of comparison, but experimentally, and when we regard as the basal problem of morphology not phylogenetic development, but the essence of development in a large sense. Even if we had the story of development spread out clearly before us, we could not content ourselves with the simple determination of the same; for then we should be constrained to ask ourselves, how it has been brought about. But this question brings us straight back to the present, to the problem of individual development. For there is for natural science hardly a more significant word than this of Goethe's: 'was nicht mehr entsteht, können wir uns als entstehend nicht denken. Entstandene begreifen wir nicht.' It is then the task of modern morphology to learn more exactly the factors upon which at this time the origin of structures depends. To this task, for which there was at that time but little preparatory work consisting of a few important attempts by the gifted Thomas Knight, Wilhelm Hofmeister, who is known to most of us only

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as a comparative morphologist, did a too little recognized service. For he pointed out, even before this trend of study became apparent in zoology, that the ill-designated 'Entwickelungsmechanik' pursues essentially the same goal as the causal morphology of botany.

We may regard as a motto this sentence from Hofmeister's 'allgemeiner Morphologie': 'es ist ein Bedürfnis des menschlichen Geistes, eine Vorstellung sich zu bilden über die Bedingungen der Formgestaltung wachsender Organismen im allgemeinen.' This is even now the problem of present day morphology. Comparative consideration, including, of course, the especially important history of development, offers us valuable preparation for the intellectual grasp of the problem, but, above all, for the pursuit of the experimental method.

That the zoologists also have felt this necessity to strike out into new ways besides that of comparative morphological observation shows anew that for all organisms the problems are really the same. Let us then take for our watchword development, not only as a problem, but also for the methods with which we seek to bring ourselves nearer its solution.

SCIENTIFIC BOOKS.

Research Methods in Ecology. By FREDERIC E. CLEMENTS, Ph.D. Lincoln, Nebraska, The University Publishing Company. 1905. Pp. xvii +384.

This work by Professor Clements is intended by the author as a handbook for investigators and for advanced students of ecology, and not as a text-book of the subject. It, therefore, contains a somewhat elaborate account of methods used by the author in his studies of the last eight years during which a serious attempt has been made by him to discover and to correlate the fundamental points of view in the vast field of vegetation.

The book is presented in four chapters or

parts, the first of which deals with the scope, historical development, present status and important applications of ecology. Under the latter caption its connection with physiology and pathology, experimental evolution, taxonomy, forestry physiography, soil physics, zoogeography and sociology is pointed out. The second chapter is concerned with the habitat and methods of its investigation. First, the factors are determined and classified and then an account is given of the various instruments, including geotomes, psychrometers, psychrographs, photometers, selagraphs, thermometers, clinometers, trechometers, etc., which are employed in the study of the habitat, together with methods of charting statistics. By these instruments and methods statistical analysis of soil water content, humidity, light, temperature, precipitation, wind, soil structure and chemistry, altitude, slope, exposure, etc., is made possible. There is attention paid to the details of choosing instruments, stations and readings. The plotting of curves and determination of graphic representations is explained. The third chapter has to do with the plant, the stimuli which it receives, the nature of its response, its adjustment and adaptation especially to water and light as stimuli. Here some experimental evolutional methods are set forth having to do with the selection of species, the determination of factors and the recording of habitat cultures and control cultures. The fourth chapter, which is the most extensive and to which the other three are in a sense preliminary, has for its general subject the formation or vegetation unit consisting essentially of plants in a habitat, the need for exact investigation of which is set forth by the author. Quadrats, transects, migration circles, are described and their use explained. The two important arts of cartography and photography in their relation to ecologic inquiry are given space, and methods of preparing and preserving formation and succession herbaria are indicated. The development and structure of vegetation are taken up under the conception that the formation is a complex organism which possesses functions and structure and passes through a cycle of development similar to that of the plant. The functions of a for

mation are described as association, invasion and succession, while its structure may comprise zones, layers, consocies, societies, etc., all of which may be referred to zonation or alternation. Thus classified, the facts and laws of migration, dissemination, barriers and indemism, polygenesis, etc., are given detailed discussion. The final pages are devoted to experimental vegetation with description of culture methods for formational aggregates.

Throughout the volume Professor Clements makes use of his carefully devised nomenclatural system, the extent of which is very considerable. A great many thousand new words and nomenclatural combinations are proposed, for the most part derivatives from the Greek. This system has already been brought to the attention of ecologists in papers in Engler's 'Jahrbücher' (1902) and elsewhere and has attracted attention. A glossary of ten pages in which the more fundamental new words are gathered is a helpful addition to the work. An index is not provided, but the glossary to some extent fills its place.

Eighty-five illustrations, for the most part half-tones, of vegetation, plants and apparatus serve to lighten up the text. Most of these are original views of Colorado vegetation prepared by the author and give a very excellent idea of the grouping of plants upon some of the mountain habitats.

Altogether, Clements's 'Research Methods in Ecology' is a notable contribution to the literature of ecology and the author is to be congratulated upon its successful delivery to the botanical world. CONWAY MACMILLAN.

The Becquerel Rays and the Properties of Radium. By Hon. R. J. STRUTT. London, Edward Arnold. 1904.

One closes Mr. Strutt's book with a feeling of rare satisfaction. The reader has had a clear and concise presentation of the fundamental phenomena of the Becquerel rays, and the phenomena centering around that astonishing substance, radium.

The book, which lays no claim to an exhaustive treatment of the subject, is primarily written for those who wish to know something about radioactivity and are interested in sci

ence.

Abstruse ideas are left out just so far as possible, and the work, although not phrased in popular language, as we understand the term to-day, is nevertheless very clearly and readably written. Mr. Strutt has evidently the faculty of presenting scientific facts in a very pleasing and attractive and convincing form. In short, he shows the stamp of the teacher.

Notwithstanding all the evident care of preparation in the work, Mr. Strutt has once or twice allowed himself to become careless in the use of terms. For example, on page 66, when treating the selfelectrification of radium, he uses the term 'perpetual motion,' stating that the above phenomena more clearly approach it than any other action we are acquainted with. It seems to me that the term is very wrongly applied, because perpetual motion means the performance of work without the expenditure of energy; and there certainly is energy expended in the above phenomena. Later on in the book (page 167) he states that 'Nothing that we can do to any portion of matter will in the smallest degree affect its weight,' etc. This is rather too loose a statement to let pass without comment.

Chapter I. discusses some general statements about the discharge of electricity through gases, a subject that Dr. J. J. Thomson has so thoroughly investigated. The discussion of the cathode and Roentgen rays contains descriptions of the various phenomena connected with them.

Chapter II. deals with the discovery of radioactivity, the first portion treating of the signal work of Becquerel, who discovered the rays which bear his name, namely, those rays which are given off by some salts, and which have photographic properties, but which differ from Roentgen rays and also from ordinary light.

The discussion of the various phenomena relative to uranium prepares the reader for the story of the discovery of radium. Mr. Strutt explains in an interesting and instructive manner the chemical procedure gone through to make it possible to obtain radium from pitchblende, a mineral in which was discovered by Madame Curie a radioactivity

far in excess of what was expected. This fact led Madame Curie to conclude that there resided in the mineral some other more active constituent than uranium.

In Chapter III. we have the properties and nature of the radiations described together with the fluorescent, chemical and physiological effects. This is followed by a rather complete discussion of the alpha rays, beta rays and gamma rays, with several diagrams illustrating experiments carried out to determine the deflection of the alpha rays and beta The experiments with gamma rays have so far been negative.

rays.

At considerable length in one of the chapters is described the subject of radioactvity in the earth and its atmosphere, a branch of the work to which Mr. Strutt has contributed rather extensively. Other chapters treat of absorption and ionization; changes occurring in radioactive bodies; the products of radioactive change.

The last chapter gives a short account of the electrical theory of matter, to which Professor J. J. Thomson has given much thought. This chapter is very suggestive and supplies food for contemplation.

At the end of the book there are three appendices, the first of which contains a number of experiments which any one may perform with a bit of radium. A sufficient amount of radium necessary for these experiments would cost in the neighborhood of twenty-five dollars. With this appendix are given two plates.

The other two appendices treat respectively of the mathematical theory of the deflection of the beta rays; a short account of the extraction of radium from large quantities of pitchblende.

The book is non-mathematical throughout, except for the appendix mentioned, and shows a keen insight into the subject dealt with. This, however, is to be expected from a man who has done so much work in the realm of radioactivity. On the whole, the book is to be commended to those who are of a scientific turn of mind, and who wish to understand clearly the principal phenomena of radioactivity. G. B. OBEAR.

PROVIDENCE, May 24, 1905.

SCIENTIFIC JOURNALS AND ARTICLES. THE American Journal of Science for July contains the following articles:

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D. A. KREIDER: Iodine Titration Voltameter.' F. A. GOOCH: Handling of Precipitates for Solution and Reprecipitation.'

R. H. ASHLEY: Estimation of Sulphites by Iodine.'

M. TALBOT: 'Revision of the New York Helderbergian Crinoids.'

L. V. PIRSSON: 'Petrographic Province of Central Montana.'

T. HOLM: Croomia pauciflora.'

E. RUTHERFORD and B. B. BOLTWOOD: 'Relative Proportion of Radium and Uranium in Radioactive Minerals.'

J. TROWBRIDGE: Side Discharge of Electricity.' H. L. BRONSON: Effect of High Temperatures on the Rate of Decay of the Active Deposit from Radium.'

THE contents of the June issue, Terrestrial Magnetism and Atmospheric Electricity, are as follows:

Frontispiece: Portrait of Karl Selim Lemström. H. GERDIEN: 'Die Absolute Messung der specifischen Leitfähigkeit und der Dichte des verticalen Leitungsstromes in der Atmosphäre.'

J. DE MOIDREY, S.J.: 'Mesures magnétiques en Chine.'

H. F. REID: 'Records of Seismographs in North America and the Hawaiian Islands.'

HJ. TALLQUIST: Karl Selim Lemström, His Life and Work.'

E. BIESE: Verzeichniss der Publicationen des verstorbenen Professors Selim Lemström.'

Letters to Editor-L. A. BAUER: 'Work of the Department of Terrestrial Magnetism of the Carnegie Institution for 1905.' W. F. WALLIS: 'Principal Magnetic Disturbances Recorded at Cheltenham Magnetic Observatory, March 1 to May 31, 1905.'

Notes- Additional Eclipse (August 30, 1905) Stations.' 'Miscellaneous.'

SOCIETIES AND ACADEMIES.

THE MISSOURI SOCIETY OF TEACHERS OF
MATHEMATICS.

THE past few years has been a very widespread movement among teachers of mathematics towards the organization of local, state and sectional associations of teachers of mathematics. This movement is both a re

sult and a cause of a very general dissatisfaction with methods of teaching mathematics in the recent past, and of various kinds of attempts to improve them. Among the many ideas that are prominently discussed are those suggested by the terms correlation, laboratory methods, individual instruction, self-activity, graphical methods, etc. The facts of modern life are furnishing material which is replacing obsolete problems. An effort is being made to bring mathematics into vital relations with the whole of life. Even the long undisturbed supremacy of the methods of Euclid in secondary education is being questioned. What will it lead to? Even the elementary teacher can not fail to see what the investigator has never lost sight of, that he is dealing not with a completed, a dead, a petrified subject, but with one of the most vigorous, living, growing subjects taught in our schools. Perhaps one of the strongest evidences that this is the case is seen in the large number of state and sectional organizations of teachers of mathematics throughout the country.

The first annual meeting of the Missouri Society of Teachers of Mathematics met at Columbia, Missouri, May 6, 1905. A prelim inary meeting had been held at St. Louis in connection with the National Educational Association. The temporary organization of the society was effected at the meeting of the State Teachers' Association at Columbia, December 28, 1904. At a meeting of the mathematics section of that body a committee of organization was appointed, consisting of E. R. Hedrick, University of Missouri, Columbia; H. C. Harvey, State Normal School, Kirksville, and B. T. Chace, Manual Training High School, Kansas City.

The permanent organization was completed at the meeting on May 6. The constitution provides that there shall be at least two meetings each year, one in connection with the annual meeting of the State Teachers' Association, the next meeting of which will be held at Jefferson City, December 1905, and one during the month of April or May, which shall be the annual meeting for the election of officers and the transaction of general busi

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