science of the results given in any paper. It goes still further, in that it summarizes the advance made during the year in each subject, and the contents of the volume are rendered still more accessible by a thorough author-genus subject index. Everything seems to be done that is possible to make the results of general biological studies available. Occasionally figures are reproduced and comprehensive, synoptic articles on the recent advances in one subject are printed. In the present volume there is a report on senile degenerescence, by Elie Metchnikov; on the urinary tubules in vertebrates, with seventeen figures, by P. Vignon; and on the conditions of existence in and the bionomic divisions of fresh waters by G. Prouvot. The reviews are all signed by the authors, the critical remarks being bracketed. Many of the reviews have the dignity of distinct contributions to science, as where a half-page abstract is followed by a two-page discussion. The reviewers, or 'collaborators,' are drawn from various countries, America, Austria, Belgium, England, Russia and Scotland being represented in addition to France. This periodical may be commended in the strongest terms to biologists and to others interested in the results of biology. It is surprising that the work is still so little known in this country. Scientific men have a right to take pride in the unremunerative efforts of the chief editor, Professor Delage, to make accessible the literature of the science of general biology in order to facilitate its advancement.
ASTROPHYSICS.
The 'Atlas of Representative Stellar Spectra, together with a Discussion of the Evolutional Order of the Stars,' by Sir Wm. Huggins, K. C. B., and Lady Huggins (Wesley & Son), is not only a sumptuous and beautifully illustrated volume, but is also of great scientific value. Sir Wm. Huggins belongs to that group of men in England who, unconnected with any university, devote themselves to research for the pure love of truth. His distinguished services to science received recognition on the occasion of the Queen's diamond jubilee, when with only two other scientific men he received the order of knighthood. His accomplished wife, who is his constant coadjutor, was the only woman mentioned in the list of Jubilee honors. Sir Wm. Huggins may be said to be the founder of the so called 'New Astronomy,' for scarcely more than a quarter of a century ago his spectroscope, turned upon a newly discovered star, first revealed the cause of the sudden lighting up of these beacons in the heavens, and turned upon the nebula showed them to be of glowing gas. Since that time the telescope of the Tulse Hill Observatory, armed with spectroscope and camera, has been constantly and laboriously analyzing the light of star, comet and nebula, to solve the mystery of their constitution. "We never go anywhere," said Lady Huggins; "astronomy, at best, is a heart-breaking object of devotion beneath English skies, and we are always at home to catch every gleam between the clouds."
This book gives, in charming narrative, which would be read with interest by one previously ignorant of the subject, the history of the pioneer work "when nearly every observation revealed a new fact, and almost every night's work was red-lettered by some discovery."
There follow full details of later work, especially of the first detection, by the shifting of the lines of their spectra, of the motion of stars towards us or from us in the line of sight. We learn also how terrestrial chemistry has been enriched by this study of the stars, and how the nature of long known elements like hydrogen and the existence of undiscovered elements like helium have been first made out from stellar spectra.
But, as the supreme problem for the biologist is the development of man, so the supreme problem for the astronomer is that of the evolutional order of the
