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SAJ UHIl 



[March 23, 191 1 



MEDICAL liioLor.y. 

 Biology, General and Medical. By Prof. J. McKar- 

 land. Pp. 440. (Philadelphia and London : W. B. 

 Saunders Co., 1910.) Price 7s, 6d. net. 



1JKOF. McFARLAND tells us in his preface that 

 " medical science is, in fact, a branch of bio- 

 logy, and should be studied as such." With this 

 opinion we heartily agree, and we were fully prepared 

 to find that the present volume would supply a long- 

 felt want in demonstrating the importance of biological 

 studies from the medical point of view. We still 

 believe that the author has succeeded in doing this, 

 but he has also succeeded in demonstrating the fact 

 that a medical man is not always the most trustworthy 

 authority on biological questions. The plan of the 

 book is interesting, and, to some extent, original, 

 commencing very appropriately with the cosmical 

 relations of living matter and ending with a chapter 

 on senescence, decadence, and death ; and the author 

 has successfully avoided the pitfalls of the type- 

 system. Nevertheless, we can hardly share his some- 

 what curiously expressed hope " that the writing will 

 not be found too technical to be beyond the compre- 

 hension of any intelligent reader." 



The work is largely a compilation and is of a 

 curiously mixed character, derived partly from text- 

 books — some of a very elementary character — and 

 partly from highly technical writings of a more or less 

 controversial nature. For elementary zoological facts 

 the author appears to have relied largely upon 

 Masterman's "Elementary Text-book of Zoology," 

 and Galloway's " First Course in Zoology," from 

 which numerous illustrations are borrowed. The 

 " New International Encyclopaedia " has supplied a 

 superfluity of information upon parasites, arranged 

 zoologically, but we should be sorry to attribute 

 responsibility for the author's statements to any of 

 the works mentioned. 



The theory of heredity is treated mainly by means of 

 copious quotations from Herbert Spencer, Darwin, 

 Galton, Weismann, and Adami. The amount of space 

 devoted to the complicated lateral chain theory of the 

 last-named author seems quite out of proportion to 

 that given to other subjects. 



We are obliged in justice to our readers to point 

 out that the work contains numerous inaccuracies and 

 misleading statements. Thus, for example, the shell 

 of a tape-worm egg is described as a cell-wall; 

 flagella and cilia are described as rigid protoplasmic 

 threads; the shells of Foraminifera and Radiolaria 

 are said to " find their homologues in the dermal cover- 

 ings, the limbs, and fins, &c., of the higher animals " ; 

 the medusa of Obelia is said to have a water-vascular 

 system, and so on. On p. 103 we are told that the 

 germinal cells have twice the number of chromosomes 

 possessed by the somatic cells, and our astonishment 

 at this statement is only partially abated when we 

 come to p. 189, and find that the author is referring 

 to the doubling of the number of chromosomes which 

 is supposed to take place in the maturation of the 

 germ-cells prior to reduction, and fully realises that 

 the actual gametes have only half the somatic number. 



It is, perhaps, of no great consequence to the 

 NO. 2160, VOL. 86] 



general reader or to the medical man if the sponges 

 are defined as "characterised by many incurrent open- 

 ings and only one excurrent opening. Axially sym- 

 metric. Sexually reproductive," but this diagnosis is 

 «o strikingly inadequate, and to some extent 1 

 incorrect, that it might just as well have been omiti<.., 

 as might that of the arthropods, which are simply 

 defined as "jointed animals." Moreover, it is always 

 possible that the book may find its way into the hands 

 of a student preparing for examination. 



In the chapter on the origin of lift 

 suggests (or borrows the suggestion, it is not quite 

 clear which) that the power of reproduction may be 

 "only characteristic of such forms as shall have 

 already evolved to a certain point." The possibility of 

 organic evolution without reproduction is, we must 

 confess, a new idea to us, and one upon which we do 

 not think, with the author, that "it may not be un- 

 profitable to speculate." 



We can only hope that the more especially medical 

 chapters, dealing with blood relationship, infection and 

 immunity, will be found less open to criticism at th. 

 hands of medical readers. A. I 



GEOLOGICAL ESSAYS. 



Otitlines of Geologic History, with especial reference 

 to North America. A Series of Essays involving a 

 Discussion on Geologic Correlation presented before 

 Section E of the American Association for the Ad- 

 vancement of Science, in Baltimore, December, 

 1908. Symposium organised by B. Willis; com- 

 pilation edited by R. D. Salisbury. Pp. viii + 306. 

 (Chicago: University of Chicago Press; Lond 

 Cambridge University Press, n.d.) Price 6s. n< 



SOME of the best qualified geological writers and 

 workers in America, including Dr. F. D. Adams 

 from the Dominion of Canada, have here brought 

 together their views on the correlation of stratified 

 deposits. The series of essays was originally pub- 

 lished in the Journal of Geology, and forms a text- 

 book of North American stratigraphy, embodying 

 results up to December, 1908. It is illustrated by 

 Mr. Bailey Willis's " paleogeographic maps" of North 

 America, which are a little difficult to read in their 

 black and white shaded form. Our ignorance of what 

 lies beneath the oceans probably gives a false impres- 

 sion of fixity to the continental boundaries in many 

 cases. 



The terminology used has been left to the various 

 authors, so that we may welcome Mr. Willis's reten- 

 tion of "Cambrian" as against Mr. Grabau's 

 "Cambric." Prof. Salisbury, as editor, points a 

 warning finger towards Mr. Grabau's preferences on 

 p. 44 ; but he is unable to save us from the " Beekman- 

 townian " representative of the " Lower Ordovicic." 

 Should not, by the by, the correct translation of the 

 French " Plaisancien " be, not Prof. Osbom's 

 " Plaisancian " (pp. 216 and 262), but either " Plm 

 tian " or " Piacenzan "? 



We have the benefit of the views both of Dr. 

 Adams and Prof. Van Hise as to pre-Cambrian classi- 

 fication. The former urges that the break between the 

 Middle and Upper Huronian in America is at lea«t 



