To the zoölogist the volume will be of no use, as it embodies few new observations on the fishes considered and is largely a compilation from other well-known works. The author, however, deserves credit for bringing the subject to the attention of anglers in such an attractive form; and, as an attempt to extend the knowledge of the habits, distribution and relationships of our game fishes among this large and influential class of citizens, the volume should be accorded a welcome.
MICROSCOPY OF DRINKING-WATER.
Mr. G. C. Whipple, Director of the Mount Prospect Laboratory of the Brooklyn Waterworks, has prepared a handbook for the water analyst and the waterworks engineer, with the title given above. It deals with the purposes, methods and results of the biological examination of drinking-water, affording means for the identification of the microscopic life found in water supplies and suggesting means for the elimination or control of those organisms which disagreeably affect the color or odor of potable waters. The construction of reservoirs, the storage of surface and of ground waters and the growth of organisms in pipes are also discussed. Though the motive of the book is thus technical, the subject is developed by the author along broad lines in a thoroughly scientific manner, and he has brought together a great deal of information, not only for the sanitary engineer, but also for the physicist, the chemist and the biologist. The problems in limnology, such as the temperature, stagnation and circulation of reservoir waters; the distribution and relative numbers of different organisms and their relation to chemical analyses are discussed in the light of the results of many years’ investigation of water-supplies. The seasonal succession of organisms, their movements with respect to light and other stimuli, and their horizontal and vertical distribution, are in like manner fully treated. The scope of the work and the treatment of the subject make the book a valuable one alike for engineering and biological laboratories and for the general library.
THE PROGRESS OF SCIENCE.
The summer laboratories and the scientific expeditions which are employing the vacation period of the men of science in this country would make a long list. A vacation from teaching means to the scientific man a chance to work, and at present there are numerous organized means of enabling him to profit by this chance. The most definite form which such arrangements for summer work have taken is the summer laboratory or experiment station for biologists. Such a station affords conveniently the mechanical appliances for scientific work in a good locality for collecting material to work with. The marine or other forms of life are thus made accessible to those whose professional work during the year keeps them in an unfavorable locality. Besides the laboratory at Woods Holl, which is the nearest American representative of Professor Dohrn’s great laboratory at Naples, there is an important summer station at Cold Spring Harbor, Long Island, under the auspices of the Brooklyn Institute, and others cared for by Leland Stanford, Jr. University, the University of Indiana, the Ohio State University and other institutions. It is common to combine teaching with research at these laboratories and in some cases they become essentially summer schools, though generally giving courses of a higher order than the ordinary summer school for nature study. But research is often the chief and sometimes the sole purpose of these stations, and a vast amount of work is done each year. The most important of these summer stations is the Woods Holl Marine Biological Laboratory, situated on the southern coast of Massachusetts, between Buzzard’s Bay and Vineyard Sound. This laboratory has been fortunate in having been the summer home at one time or another of a majority of the leading zoölogists of the country. It has been usual for the advanced students in universities to take courses or carry on research there, and Woods Holl training has been a valuable recommendation. The reason is not far to seek. The material advantages, the spirit of zeal for concrete fact, the acquaintance with superior men in the science and with a large number of equals, all help to give the best sort of professional training. Such a place also serves as a refinery where opinions and theories may be purified by healthy criticism and by the subtler influence of example. There is a story of three eminent biologists who got involved in a controversy over a disputed question. They argued for a while. Finally one of them said: “Let us get the eggs in question and study them together.” This was done, and the three men spent the afternoon over their microscopes patiently working out the problem together; and they did work it out. One of the great advantages of summer laboratories is that they put fellow-students in a frame of mind in which they can work things out together.
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The Woods Holl Laboratory has a right to claim a large share in the credit for three of the most important developments in biology in the last decade—the study of ‘cell lineage,’ of regeneration of organs and of the influence of abnormal conditions on the development of embryos. Workers there have traced the development of the different cells into which the egg-cell divides and have discovered just what parts of the body arise from each group of cells. They have shown that the way in which the egg divides and redivides is as constant, is as much a part of the nature of the animal, as its adult form and structure are. They have replaced previous vague notions of the development of animals by exact accounts of the cell-origin of different organs of the body. Others have studied the abilities of mutilated animals to reproduce the parts lost and the conditions and limitations of such regeneration. Such studies have greatly broadened our views of the nature of animal tissues. Others have investigated the results of artificial conditions on the development of animals, especially in the earliest stages. For instance, from eggs broken into pieces there have been developed twins, triplets and monsters of various sorts. Such experiments as these are producing data concerning the very fundaments of living matter and are leading biology beyond the mere description of animal structures and functions towards an insight into the elementary principles of development. Among the numerous researches, some seventy in all, which are being carried on at Woods Holl this summer, those of the most general interest are Prof. C. O. Whitman’s study of hybrids and Prof. Jacques Loeb’s study of artificial fertilization. Prof. Whitman has been breeding pigeons of a large number of species for several years, as a means of studying the phenomena of heredity shown in hybrid forms. More or less incidentally, he has discovered many notable facts about the instincts and habits of the birds and about various physiological functions connected with reproduction. Biologists everywhere are coming to realize the necessity of systematic and continuous study of families of animals through a number of generations. Prof. Whitman’s is the most extensive of such studies in this country. The detailed results of Prof. Loeb’s continuation of his experiments on the action of various salts on unfertilized eggs will naturally be awaited with great interest. We have already noticed his success in causing unfertilized eggs of the sea-urchin to develop into normal individuals as far as the pluteus stage. He has this year succeeded in producing artificial parthenogenesis not only in starfish (Asterias), but also in worms (Chaetopterus). Through a slight increase in the amount of K-ions in the sea-water, the eggs of the latter can be caused not only to throw out the polar bodies as Mead had already observed, but also to reach the Trochophore stage and swim about as actively as the larvæ originating from fertilized eggs.
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