2 [ 2 



NA TURE 



[August 19, 1909 



.sense, of every other sintjle criterion which could be 

 applied. 



These, however, are small points. Summing- up 

 one's impressions of the book as a whole, they are 

 that it well maintains its place in the front rank of 

 works devoted to the study of oils, fats, and waxes. 

 To the chemical technologist it is practically indis- 

 pensable. C. SiMMONDS. 



A CYTOLOGICAL TREATISE. 

 Plasma und Zelle. Erster Abtheilung. Bv Prof. 



.Martin Heidenhain. Erste Lieferung, Die Grund- 



lagen des mikroscopischen Anatomie, die Kerne, 



die Centren, und die Granulalehre. Pp. viii + 500. 



(Jena : Gustav Fischer, 1907.) Price 20 marks. 

 T^HIS somewhat bulky volume is the first instal- 

 -^ ment of Prof. .Martin Heidenhain's treatise on 

 " Plasma und Zelle " which is to form a part of 

 Bardeleben's great work on human anatomy. 



The method which the author has adopted is 

 perhaps not the ideal one, but it must be remembered 

 that the science of cytology is young, and its vigorous 

 development has manifested itself in the growth of 

 an enormous amount of details which some day will 

 become connected up so as to make a coherent or- 

 ganism, despite the fact that at the present time the 

 different sections seem to be somewhat isolated. The 

 features which in one group appear to be of funda- 

 mental importance may elude recognition in, and 

 perhaps be really absent from, others ; and thus that 

 logical connection so dear to the minds of many is 

 difficult, and at present often impossible, to trace. 

 Probably for some time to come the trees will be 

 more apparent than the wood. Prof. Heidenhain has 

 chiefly worked on the cells of a few vertebrate 

 animals, and it must be confessed that throughout the 

 somewhat lengthy treatment of his subject this point 

 of view is rather strongly reflected. There is hypo- 

 thesis in plenty, together with much reallv acute 

 analysis, but one cannot repress the feeling that the 

 chastening influence of the protozoan nucleus is rather 

 conspicuous by its absence. 



The treatment is frankly morphological, and upon 

 a somewhat narrow range of very detailed observa- 

 tion of comparatively few forms a theoretical super- 

 structure of doubtful stability has been erected. Some 

 cytologists, at any rate, will criticise one of the earlier 

 pronouncements (p. 3) in the book, to the effect that 

 discussion (Erorterung) of biochemical structure forms 

 no part of the province of scientific morphology, and 

 that the latter must take the former as granted. 

 Surely the trend of modern morphology is in the direc- 

 tion of discontent with such a position. Some of us, 

 at any rate, believe that form and structure are merelv 

 the expression of biochemical constitution, and it is 

 just this latter problem that we want to attack. 



Prof. Heidenhain postulates " units of living sub- 

 stance " as the essential elements of an organism. 

 The cells are regarded as a special case of the aggre- 

 gation of these living units. In this he is practfcally 

 following those who regard the cell as by no means 

 the real unit of the organism, and unquestionably this 

 is a tenable position ; but, nevertheless, the cell, despite 

 NO. 2077, '\'OL. 81] 



its complex organisation, represents actually the 

 lowest rank in the polity of the multicellular organism 

 out of which the organism itself is built up; nor is 

 the case really different in syncytial bodies. The 

 quarrel with the cell from this point of view is perhaps 

 partly due to the fact that we have not been clear as 

 to what we mean by an organism. A human society 

 is made up of the individuals which compose 

 it; we are justified in regarding them as the 

 ultimate constituents of such a social organism 

 and we cannot usefully push our analysis further 

 back, for they form the lowest units which 

 [jropagate themselves and differentiate into the 

 comple.K structure of which the society is composed. 

 Of course, we are aware that each one can be resolved 

 still further into tissues and cells, but these things 

 do not come into the scheme of the social organism 

 as such. The same holds good when we get still ' 

 lower in the scale. The cells plainly continue to' be 

 the units of which the corpus is built up — until we 

 get to the unicellular organisms. In the latter we 

 find a more elaborate differentiation than is char- 

 acteristic of the metazoan or metaphytan cell, but in 

 essentials it seems to be the same. The protoplasm 

 and the nucleus still are requisite to maintain it as 

 a going concern, and reproduction by fission or other- 

 wise is always connected with the distribution of a 

 combination of both to each of the offspring. This 

 is strikingly shown in some forms in which a nucleus 

 as such is perhaps absent, and only the stuff of which 

 the nucleus is made is present in a more or less dis- 

 tributed condition in the cell. 



But although we may not agree with the author in 

 his belittlement of the cell, many will assent to his 

 conclusion that it has been made too prominent as 

 the " be all and end all " of the living body. The 

 organism is higher than its parts, and itself determines 

 what form it shall take — or, to put it more plainly, 

 the reactions that are due to the relations subsisting 

 between one part of the organism and another, or 

 between it and its environment, are of such a kind 

 as to influence the fashion of development of the new 

 cells and new tissues. 



Prof. Heidenhain's position with regard to the cell 

 is clearly stated on p. 81, where he says that 

 " it is not the cell which is the bearer of life, but 

 life is inherent in every living particle, down to the 

 smallest molecular group which can be called alive. 

 The cell is rather only a special apparatus which itself 

 is made up of living material." 



The crux of the matter obviously lies in the mean- 

 ing we attach to the word " living." 



Many pages are devoted to cell organs, such as 

 centrosomes, and to a very lengthy discussion of 

 .Mtmann's so-called " granular theory." We confess 

 that much of the space thus allocated seems to us to 

 be hardly well utilised; and although it is not fair 

 finally to criticise a work of which only the first part 

 has appeared, it appears to us that a more real service 

 to cytology would have been rendered if Prof. Heiden- 

 hain had focussed the information which is so rapidly 

 accumulating as the result of the study of the lower 

 forms of life upon the problems presented by the 

 higher types. 



