EDITORIAL. The comparative method is one of the distinguishing characteristics of modern science. Nowhere has it been more fruitful in its application than in the natural sciences, which assume the unity of nature. Comparison here means that in the midst of the detailed analysis to which science subjects natural phenomena there is an accompanying synthesis. Things, to be compared, must be at once different and yet related. The aim of the comparison is to state more comprehensively the relations as well as to define more accurately the differences. But it is in the biological sciences that the comparative method becomes conspicuously serviceable, since here the doctrine of evolution has come in to reinforce the idea of nature as a unity or system. Here unity means continuity, function becomes significant only through genesis, physiology through morphology, and homology gives to comparison a meaning it never could have had so long as it expressed simply superficial resemblance. But a still further step is implied in the comparative method, a step which is best represented in what have been called the hyphen sciences such as astro-physics. physical-chemistry, psycho-physics, physiological-psychology. Without prejudging a movement which is still in its infancy, it may be said that the significance of this tendency is likewise toward an organic interaction between the various sciences, an interaction which promises to be most fruitful and, in the present period of scientific specialization, is greatly needed. It is one aim of this Journal to contribute to this development of the comparative method by bringing together researches which, both from the structural and the functional sides, will show what is meant by the evolution of action. * * Action is a category common to all science, whether we are dealing with the motion or energy of physical science, with the "reactions" so-called of living organisms in the case of tropisms, reflexes, and instincts, or with the "mental processes” or "mental activity" so vaguely conceived at the present time under the figure of a "stream of consciousness." OSTWALD'S recent attempt to subordinate the psychical to the idea of energy is indicative of the demand for a category of action which may serve as a platform upon which the various sciences may get together to discuss those important problems where their respective fields overlap. BALDWIN'S Conception of "psychophysical evolution" and of "bionomic" and "psychonomic" forces is a similar attempt to find a basis upon which we can discuss the problems of mutual interest to biology and psychology, without raising metaphysical issues. The evolution of action, then, in the application of the comparative method to neurology and psychology, means the evolution of the organism, especially of the nervous system, as a machine for converting stimulus into response, as a mechanism susceptible to, and in turn mediating, measurable changes in the phenomenal world. Whether mental process is simply a phase of action and, if so, in what sense this is true, are questions which here are not raised, the position taken by this Journal being simply that for the comparison of the mental and the neural, the two sets of phenomena must be facts of the same order. The facts of comparative psychology, as truly as the facts of comparative neurology, are acts or reactions, whether or not, in the last analysis, we distinguish the "psychic" as distinct from the "psychological" and "physical" facts, which latter are here brought into comparison. ** The Carnegie Institution has established a Department of Experimental Biology under the charge of Professor C. B. DAVENPORT, now of the University of Chicago. In this Department two Stations have already been arranged for. One a t the Dry Tortugas, Florida, under charge of Dr. A. G. MAYER, will undertake the investigation of tropical marine faunas. The other at Cold Spring Harbor, Long Island, will be devoted to an experimental study of evolution. This Station will be on the grounds lying between the New York State Fish Hatchery and the Biological Laboratory. About twelve acres of ground have been leased for a period of 50 years and through the cooperation of generous neighbors the use of much additional land, both forest and pasture, will be available. A building of brick, about 35 by 60 feet, will be erected on the ground to serve as administrative quarters and for the breeding of some of the smaller animals and plants. An experimental garden of about an acre, completely covered from access of birds by wire netting will be started at once, and there will be two acres of supplementary gardens. The staff of the Station will consist of Professor DAVENPORT as Director (who will retain for the present also the direction of the Biological Laboratory); Mr. FRANK E. LUTZ, who will have charge chiefly of biometrical variation investigations; Dr. GEORGE H. SHULL, who will work chiefly on plants, and of Miss ANNA M. Lurz, who besides serving as secretary will make certain cytological investigations. The output of the Station will be increased by others residing there for a greater or less part of the year. Professor R. S. LILLIE will thus be in residence during 1904-05. There will also be a class of Associates which will include biologists who receive special aid for work in Experimental Evolution from the Carnegie Institution or whose work is aided by the Station. The Station and its Associates will coöperate in the work and the results of the investigations of the Associates will, in so far as aided by the Station, be published as results of the Station. The lines of investigation to be taken up by the Station inIclude not only the evolution of morphological characters but also of physiological ones. Especial attention will be paid to the question of the limit of inheritableness of acquired characters, both static and dynamic. It hoped that results of importance for Psychology and Neurology will be gained of which the readers of the Journal may expect duly to be advised. COLOR VISION. The frequent appearance of new theories of color vision is sufficient proof that there is still a feeling of dissatisfaction with the theories chiefly in vogue. The most recent candidate' for public favor has been somewhat caustically reviewed by Mrs. LADD-FRANKLIN in the Psychological Review (X, 5, Sept., 1903) and, as the monograph is still incomplete, notice is withheld. But the occasion is opportune for calling attention to the very excellent and useful summary of this subject published by Professor MARY WHITON CALKINS in Arch. f. Anat. u. Phys., Physiol. Abt., Suppl. 1902, entitled "Theorien über die Empfindung farbiger und farbloser Lichter." We desire, however, first to call attention to what we deem a fundamental error (often in language only, it may be admitted) which serves to introduce more or less confusion into all of the current discussions. Considered from the purely psychic point of view, such a thing as composition or "mixing" of sensations is impossible, and this will apply with special force to color sensations. As a matter of fact-of immediate experience—any color, shade or tint is a separate discrete fact of apprehension. From a score of shades of red we may select any one as an objective unit and no one of the twenty will be experienced as a mixture. If it be a fact that there are four primary colors in the spectrum by the mingling of which all secondary colors can be produced, this mixing is not a psychological mixing (though it is a psychological mixing so to describe it) and the fact in no way disproves the statement of the discrete and separate character of every color sensa Black has just as real an experimental independence as though it had a definite wave length as its external occasion. That this should be so is readily seen on the basis of the writer's equilibrium theory of consciousness. If every conscious state is but the result of an equilibrium of the cortical activities involved, it makes 1 EGON RITTER VON OPPOLZER. Grundzüge einer Farbentheorie. Zeits. f. Psychol. u. Physiol. d. Sinnesorgane, XXIX, 3, 183-203. no difference whether one color impression was acting or a dozen were coöperating to impress their mode as the dominant in the equilibrium. The result in either case would be a unitary impression or feeling. But is it not true that all shades of green, for instance, are recognized as phases of one color? To a certain extent this is true. Different kinds of green are all called green, though when placed side by side they seem to differ greatly. But it is impossible for me to say that one out of the many is a pure green and the others are mixtures. It does not appear that there is a composition of simple sensations of which one element (say in this series of greens) remains constant and serves to label all of these nuances "green," while a variable element affords a means of identifying, one as emerald green and another as grass green, etc. In fact, it is possible to arrange a series of shades which pass imperceptibly from green into blue, as would not be the case if green and blue were fundamentally different sensations in any other sense than are various sensations of green. Such fusion as there is must be infra-conscious-a nervous process or, at least, a process below the threshold of consciousness. Professor CALKINS, in criticising the HELMHOLTZ theory of color, says "Yellow looks to us simply yellow and does not in the least appear like a mixture of red and green nor like any other color mixture." We would go farther and add that any color or shade whatever looks like itself and by no means like a mixture of other colors. If various shades of green, e. g., resemble each other more than they do some other primary color this is a subjective fact by itself as is the very fact that certain nervous processes give rise to the mode "green" rather than some other mode of sensation (a fact wholly inexplicable like any "genetic mode"). But, as a matter of experience, some shades classed as green resemble some shades classed as blue more than they do the extreme shades of green. The fact of such resemblance is not to be explained as the result of mixture but as the result of the power of a certain range of color-stimuli to awaken, concomitantly with their color sensations, accessory activities and to call them into sympathetic vibration in the equilibrium. The basis of resemblance and difference perception is undoubtedly cortical and is a function of the equilibrium resembling those elements upon which we base judgments of position, etc., even though they are not separately perceived. Now if we attempt a discussion of the nature of the analysis of light into what are called primary colors we are at once struck by the fact that light itself affords us no such analysis. A light wave is not a |