Page:Popular Science Monthly Volume 10.djvu/521

Rh has had one birthplace, and only one, the second and third chapters discuss the means by which dispersal has been effected, and what bearing the surface-changes of the earth have had on distribution. They are of great interest, and admirable examples of the efficiency of scientific induction when applied by able hands to the solution of perplexing problems.

The principles upon which zoölogical regions should be formed are next considered, and the reasons given which led the author to adopt, with little change, the divisions proposed by Mr. P. L. Sclater in 1857, which maps the globe into six great primary regions, the Palæarctic, Ethiopian, Oriental, Australian, Neotropical, and Nearctic.

Zoölogical classification receives, as of course it should, due consideration. Mr. Wallace attempts no reconciliation of the disputed points of classification, but selects and tabulates for his uses a few of the best known classes. As the title-page indicates, the relation and distribution of extinct faunas have an important place. The recent lectures of Prof. Huxley are too fresh in the minds of our readers for it to be necessary to emphasize the value of the study of fossil forms in connection with the general doctrine of evolution. In the hands of Mr. Wallace its application to the question of distribution is full of suggestion and interest. We may add that, in this connection, due acknowledgment is made of the successful and important labors of American paleontologists.

In Parts IV. and V. are treated, first, the forms of life as seen in the different zoölogical regions, their differences and resemblances being pointed out; with, lastly, a systematic, tabular arrangement of the families of the animals considered, and sketches of their geographical distribution. The value and interest of these volumes are enhanced by a series of twenty plates showing the physical aspect and special zoölogical character of the different sub-regions, and by a set of excellent maps on which are shown the outlines of the regions and sub-regions, the belts of altitude, the forests, pastures, deserts, and snow-lines, together with the contours of the beds of the great oceans as determined by the most recent soundings.

a communication made in 1869 to the Philadelphia Academy of Sciences, Dr. Lea, in this pamphlet, gives the results of further examination of the crystals and cavities to be found in gems and minerals. His special researches are illustrated by a plate in which are represented cavities of all shapes, with and without fluid contents, crystals of various shapes and maculations in corundum, sapphire of different shades, zircon, moonstone, emerald, where the cavities contained cubic crystals surrounded by a fluid, and beryl with irregular imperfections. The microscopic study of gems must possess great interest to any one whose opportunities allow it.

papers which make up this book originally appeared in the Phrenological Journal and other publications, and embrace discussions on subjects relating to physics, astronomy, biology, social science, religion, etc. "The essays are chiefly intended to uphold the theory of the stability of matter and forces, and the perpetuity of all minds, as material forces, on a new basis of reasoning, in opposition to the many present vague theories of spirit-minds. Also, as opposed to the assumed origin of matter from nothing, and its inevitable extinguishment in time—not mere change of form and action, but utter annihilation being claimed by some." The author vehemently opposes the "debasing, stagnant theology of over eighteen centuries," deprecates the "folly of Biblical cant," and believes that the "Christian religion is an old-times crude theology and false cosmogony, that ought to be replaced by a more rational and ennobling conception and worship of an infinitely intelligent great First Cause, who is known to us through his creations, and thus inferred attributes of infinite goodness, wisdom, and power."

Various theories are presented in regard to different subjects, which are not wonderful so much for their novelty as for the obscure manner in which they are stated.