May 22, 19 1 3] 



NATURE 



!93 



Of the three elements carbon, hydrogen, and 

 oxygen, the author concludes that: 



" Each by itself, and all taken together, possess 

 unique and preeminent fitness for the organic 

 nechanism." 



Nor is the ocean forgotten, but comes in for a 

 whole chapter and a warm encomium. The latter 

 part of the book is devoted to a discussion on 

 vitalism and teleology, and the author uses the 

 "fitness " of things physical as an argument for a 

 mechanistic interpretation of things organic. For 

 the "fitness" of the physical world appears to 

 'imply teleology. Nevertheless, mechanism is 

 enough. Hence the semblance of teleology is 

 misleading, and therefore mechanism must suffice 

 for biology also. Perhaps Dr. Henderson's 

 position with regard to vitalism may best be illus- 

 trated by the remark of Laplace, which he him- 

 self quotes. When the philosopher was asked 

 by Napoleon why the name of God did not occur 

 in his Mecanique celeste he replied: "Sire, je n'ai 

 pas besoin de cet hypothese." 



(4) Prof. Minot's book is the outcome of six 

 lei lures delivered by him at Jena in the capacity 

 of "Exchange-Professor." After a preliminary 

 lecture on the nature of cells he develops his views 

 on the changes that occur in the life cycle from 

 fertilisation until death. With fertilisation comes 

 the inception of a process of rejuvenescence 

 characterised by the formation of a number of 

 undifferentiated cells, and with a great propor- 

 tional increase in the total amount of nuclear 

 material in the organism. Then comes a stage 

 where the tissues develop, where they undergo a 

 process of differentiation or cytomorphosis, as the 

 author terms it. This is eventually followed by 

 degeneration and ultimately by death. Death is 

 the price paid for differentiation. Such is the tale. 

 We rot and rot, but Prof. Minot sees the rotting 

 starting earlier than the poet does. Senescence is 

 the outcome of cytomorphosis, and as this is most 

 active in comparatively early embryonic stages it 

 follows that we are rotting most rapidly before we 

 are born. After that we are let down more gently. 

 The book rambles a good deal, and a chapter is 

 devoted to the determination of sex, though it 

 seems scarcely germane to the main thesis. 

 Possibly it owes its place to its being an attractive 

 subject for a course of semi-popular lectures. 



(5) The last edition of this well-known work 

 appeared in 1904, and was reviewed in Nature for 

 June 29, 1905. The greater part of the present 

 edition is a reprint of the earlier one, but in one 

 respect there is a change. Lectures 22-24, deal- 

 ing with heredity, have been rewritten, and a fresh 

 lecture added. The change was necessitated by 

 the great progress made in these studies during 



NO. 2273, VOL. 91] 



the past few years owing to the discovery of 

 Mendel's work. Weismann's second edition 

 appeared four years after that discovery, and the 

 matter was then dismissed in a few lines. To-day 

 the position is accepted, and the author endeavours 

 to bring the new facts into line with his theory. 

 That the conception of segregation fits in a general 

 way with his views on the nature of chromosomes 

 is obvious. But, as he himself recognises, diffi- 

 culties begin to appear as soon as the matter is 

 more carefully considered. 



One of the difficulties at the root of the chromo- 

 somal interpretation of hereditary factors is the 

 fact that in some species already, e.g. Triticum, 

 Lathyrus, and Antirrhinum, the number of factors 

 identified is greater than the total number of 

 chromosomes. Some investigators, notably 

 Morgan, have sought to reconcile such cases with 

 the chromosome hypothesis by means of Jansen's 

 theory of "chiasmatypie," while others are in- 

 clined to question the sufficiency of the chromo- 

 some theory to explain segregation. Fresh facts, 

 however, must decide the matter, and it is likely 

 that the next few years will be critical years for 

 Weismann's views. The present volume is of his- 

 torical interest in showing the attitude of a great 

 speculative mind when brought to face a new and 

 unfamiliar body of facts, and it is much to be re- 

 gretted that in shaping their interpretation a brain 

 of such synthetic capacity is little likely to be 

 available. 



VON RICHTHOFEN'S "CHINA." 

 China : Ergcbnisse eigener Reisen und daranf 

 gegrimdeter Studien. Von Ferdinand Freiherr 

 v. Richthofen. Dritter Band. Das siidliche 

 China. Herausgegeben von Ernst Tiessen. Pp. 

 xxxi + 8174- 5 plates. Fiinfter Band. Enthaltend 

 die abschliessende palaeontologische Bearbeitung 

 der Sammlungen F. von Richthofens, die Unter- 

 suchung weiterer Fossiler Reste aus den von 

 ihm bereisten Provinzen sowie den Entwurf 

 einer erdgeschichtlichen Uebersicht China's. By 

 Dr. Fritz Freeh. Pp. xii + 2894- 31 plates. 

 Atlas von China. Orographische und geologische 

 Karten von Ferdinand Freiherr von Richthofen, 

 zu des Verfassers Werk "China: Ergebnisse 

 eigener Reisen und darauf gegriindeter 

 Studien." Zweite Abtheilung. Das siidliche 

 China (zum dritten Textband gehorig). Bear- 

 beitet von Dr. M. Groll. Pp. 12 + plates 27-54. 

 (Berlin: Dietrich Reimer, 1911-12.) Price, 



Bands III. and V., 32 marks; Atlas, 52 marks. 



'"F^HESE volumes complete what may well be 



_L called the monumental work of Baron v. 



Richthofen on China, for the word is equally 



appropriate whether we regard the extent and 



