246 



THE POPULAR SCIENCE MONTHLY 



of the law of natural selection, they are fos- 

 tered, cared for, and allowed to propagate 

 their kind. " Society preserves for the pro- 

 genitors of the future alike the weak, the 

 strong, the diseased, and the healthy. If, 

 then, this blind law of natural selection is 

 the one key to progress, man must degen- 

 erate." One school of statistical writers 

 maintains that this result does actually ap- 

 pear. 



But Mr. Lewis shows conclusively that, 

 while " civilization does largely sacrifice 

 one principle of progress the law of 

 evolution by survivorship it introduces 

 another still more potent principle" 

 longevity. The outcome of careful breed- 

 ing for a few generations, with a view to 

 improvement in this direction, would pro- 

 duce a people who would live to a patri- 

 archal age. The idea of such stirpiculture 

 as this is repulsive to our present habits of 

 thought. It is probable that the idea will 

 never be realized, but there is a tendency 

 toward something of that kind. 



Mr. Lewis truly says that the subject 

 leads us to the door of a world of restless 

 thought and speculation. 



The paper is extremely interesting and 

 suggestive. 



Elementary Lessons in Physical Geogra- 

 phy By Archibald Geikie, LL. D., 

 F. R. S. London and New York : Mac- 

 millan & Co., 1877. Pp. 375. Price, 



$1.75. 



One of the best of the " Science Primer 

 Series " was that of Dr. Geikie on " Physical 

 Geography," which in the present volume is 

 expanded into the form of a text-book for 

 rather more advanced scholars. 



The author is undoubted authority on 

 this subject, and may be fully trusted, and 

 his material is well arranged for the pur- 

 poses of teaching. The illustrations are 

 taken close at hand, and not only show the 

 way in which effects, with which we are 

 familiar, have been produced, but teach the 

 collateral lesson that Nature's processes are 

 uniform ; that the most stupendous results 

 of far-away lands or past time have been 

 wrought by the same methods that are in 

 operation here and now. This is a lesson 

 that scientific men were slow to learn, and 

 it has not hitherto been sufficiently taughl 

 in our text-books. Jt is something gained 



when a boy, watching the little streams of a 

 summer shower making their way through 

 a sand-bank, knows that he is looking on 

 the same forces at work that make and waste 

 a continent. 



The book is freely illustrated with good 

 woodcuts, and with maps showing the dis- 

 tribution of atmospheric pressure, tempera- 

 ture, volcanoes and earthquakes, ocean-cur- 

 rents, etc. 



Geological and Geographical Survey of 

 Colorado and Adjacent Territory 

 (1875). Pp. 834. Washington : Gov- 

 ernment Printing-Office. 



It would be impossible, within the nar- 

 row compass of a book-notice, to summa- 

 rize the contents of this valuable report ; 

 indeed, the space at our disposal would be 

 insufficient even to give a simple list of the 

 many wonderful natural curiosities and in- 

 teresting ancient ruins here for the first 

 time described and pictured. Then, in ad- 

 dition to the reports of the geologists and 

 togpographers, we have an elaborate mon- 

 ograph on the American bison, by J. A. 

 Allen ; and a voluminous report by Dr. A. 

 S. Packard, Jr., on the Rocky Mountain 

 locust and other insects injurious to the 

 field and garden crops of the Western Ter- 

 ritories. 



Fur-bearing Animals. By Elliott Coues. 

 Pp. 36'2. With numerous Figures and 

 Plates. Washington : Government Print- 

 ing-Office. 



Dr. Coues has for some time been en- 

 gaged in preparing a systematic history of 

 the North American mammals, both living 

 and extinct, and the present volume is of- 

 fered as a specimen of the method of treat- 

 ment to be adopted in that work. The 

 group of animal forms described in this 

 monograph, the family Mustelidce, he divides 

 into five sub-families, namely, 3Tmielinw 

 (wolverene, marten, weasel), BTepMtince 

 (skunk), Melince (badger), Lutrince (otter), 

 Enhydrince (sea-otter). The material on 

 which the author bases his systematic clas- 

 sification is sufficiently voluminous, namely, 

 the collections made by Hayden's Survey, 

 of which he is the naturalist, and those of 

 the National Museum at Washington. The 

 purely scientific and technical aspects of 

 the subject-matter are, of course, discussed 



