256 



SCIENTIFIC NKWS. 



[Mar. i6, 1888. 



^tUt^m^* 



Animal Biology. An elementary text-book. By C. 

 Lloyd Morgan. London: Rivingtons, 1887. 



It is impossible to gain a clear idea of what "Evolution" 

 means, without an orderly and accurate knowledge of 

 some of the facts on which that great theory rests ; for 

 it is a scientific theory, and science rests wholly on facts. 

 The methods of science are the methods of observing 

 facts, of thinking about those that have been observed, 

 and of verifying the conclusions arrived at. Here we 

 have an excellent text-book, which introduces the reader 

 to some of the most fundamental facts of animal biology. 

 It puts before him the principal types, from the rabbit 

 and pigeon down to the amoeba. It traces their deve- 

 lopment, describes them as they are, and gives an account 

 of what they do — how they feed and breathe, and all 

 their parts are nourished, and how they feel and move. 

 Then by careful summaries of the most essential facts 

 the reader is led to compare the types, to relegate each to 

 its due place in the series, and to comprehend the nature 

 of the relations which hold between them. At the same 

 time the reader is warned that he must not merely take 

 on trust what he is told ; he must " repeat the observa- 

 tions and experiments . . . and conscienciously verify 

 the inferences of his masters in science." " The student 

 of science must learn his facts at first hand, and must 

 regard books as guides to that object." And indeed this 

 book is an excellent guide to that object. 



Professor Morgan's plan of putting the higher types 

 first, and devoting to them the larger portion of the 

 work, is not usual ; for most teachers of biology prefer to 

 pass upwards in the series, beginning with animal life as 

 manifested under its simplest conditions, and following 

 it in its development through forms of increasing com- 

 plexity. But the new plan is decidedly to be commended. 

 Professor Morgan states that he has adopted it " because 

 he has had in view . . . the requirements of those who 

 intend to follow a medical career ; and who will, he 

 believes, after looking through such a course as is 

 developed in this volume, be able to make a better 

 start, and thereafter more rapid progress, in their study 

 .of human anatomy and physiology than would be other- 

 wise possible. 



Hitherto those who have studied for the London Int. 

 B.Sc. and Prel. Sci., or for other similar examinations 

 based on the type system, have had no simple text-book 

 suitable for their use. This want Professor Morgan has 

 supplied in a most satisfactory manner. 



The book is written in a simple, clear, and most 

 interesting style; it is well illustrated with outline 

 sketches and diagrams which are very completely ex- 

 plained ; the summaries and comparisons which occur at 

 intervals will be of great service to the student; and 

 finally there is a very good index. 



Sixth Annual Report of the United States Geological 

 Survey, 1884-1885. By J. W. Powell (Director). 



In this volume we have the report of Mr. J. W. 

 Powell, the Director of the United States Geological 

 Survey, for the fiscal year 1884-1885, to the Secretary 

 of the Interior, detailing the progress made during that 

 time at the various centres from which surveying 

 operations are being conducted throughout the United 

 States. 



During the year, 57,508 square miles of country were 

 surveyed and maps thereof prepared, at an average cost 



of 3 dollars per square mile. The bulk of the work done 

 was in the Appalachian and Missouri-Kansas districts, 

 15,000 square miles being also surveyed in the plateau 

 region of New Mexico ; comparatively small areas of 

 Massachusetts, New Jersey, Texas, Yellowstone Park, 

 and Northern California, go to swell the total, surveying 

 in these districts having been only recently commenced. 

 The reports of the four-and-twenty heads of divisions 

 which follow Mr. Powell's report, being mostly formal 

 statements of progress effected, are not of great interest 

 to the general reader ; but five of the departments have 

 sent in accompanying papers, giving exhaustive details of 

 their respective districts, etc., which are well worth 

 attentive examination. 



The first of these is by Capt. C. E. Dutton, concerning 

 Mount Taylor and the Zuni Plateau, a volcanic district 

 to the north of Arizona and New Mexico. This paper 

 is beautifully illustrated throughout, by the photo-litho- 

 graphic process, and in special cases where it is desirable 

 to secure accurate records of the rock formation, extra- 

 ordinary trouble has been taken to accentuate the 

 important features of the original photograph ; for 

 instance, in order to show clearly the columnar structure 

 of a volcanic " neck," the following processes are under- 

 taken : "From the original negative an enlarged positive 

 or transparency was made. From this a still larger 

 negative was taken ; with the enlarged negative a silver 

 print on paper was then made, and on the surface of the 

 print a pen-and-ink drawing was traced. The drawing 

 was then bleached and the silver print dissolved out, 

 leaving only the penwork, which was reproduced on a 

 greatly-reduced scale by photo-engraving." The next 

 paper, by Messrs. Chamberlin and Salisbury, treats of 

 the driftless area of the Upper Mississippi Vallej^, and is 

 an attempt to account for the absence of glacial drift over 

 a district of 10,000 square miles in the Upper Mississippi 

 basin, the whole of the surrounding country bearing a 

 great mantle of drift that has apparently been unable to 

 spread over this favoured spot. The driftless character 

 of this region has arrested the attention of many geolo- 

 gists of repute, from the days of Owen to our own ; the 

 remarkable feature of the case being, that the district 

 which has been left untouched by the glaciation that 

 prevailed all around is a broad tract lying in the very 

 valley of the great river of the region, unprotected by any 

 topographical barrier, that could have arrested the drift- 

 bearing ice in its downward career on the slope toward 

 the unglaciated basin. We cannot say that the solution 

 of the mystery offered by the authors is entirely con- 

 clusive, which is hardly to be wondered at, considering 

 the vast area of country and its contour, which have 

 to be taken into account in speculating on a subject of 

 such magnitude ; but their paper is certainly a valuable 

 contribution to the literature of a problem which has 

 already puzzled such geologists asOwen,Daniels,Percival, 

 Irving, and many others. The third paper on the " Quan- 

 titative Determination of Silver by means of the Micro- 

 scope," by J. S. Curtis, describes an improved method 

 of measuring the resultant silver-bead of an assay with- 

 out removing it from the cupel ; an important considera- 

 tion where the proportion of silver is only about o'ooooi 

 per cent., with ten grains as the quantity of the rock taken 

 for assay. 



With the space at our disposal, we can do no more 

 than mention a paper by Professor N. S. Shaler, on 

 "Sea Coast Swamps of the Eastern United. States," 

 describing the causes of their formation, and the results 



