December 4, 1902] 



NA TURE 



99 



is well written and well printed, and the illustrations 

 are numerous and accurate, and are also beautifully 

 reproduced. By far the majority are original, although 

 the author has, not unwisely, availed himself of good 

 figures by other workers, especially in the domain of 

 vertebrate histology, which has hitherto been more 

 completely exploited than that of Invertebrata. Such a 

 book as this fills an important hiatus in our series of text- 

 books, and it is to be hoped that before long we 

 shall see an English translation. It is certainly strange, 

 considering the importance of the subject and the 

 necessity that so many workers must have felt to be 

 informed regarding what is known as to the minute 

 structure of the tissues and organs in this or that class 

 of animals, that no effort has been made, since the 

 work of Leydig, which was published as long ago as 

 the middle of the last century, to furnish, on modern lines, 

 such an account of minute structure as is ably given by 

 Dr. Schneider in this volume. Oppel's " Vergleichende 

 Histologic" deals, it is true, with a part of the subject, but 

 in a different manner, giving an account, more or less 

 historical and bibliographical, of researches which have 

 been made into the structure of particular organs and 

 groups of organs in Yertebrata, with occasional original 

 observations interspered ; while in the book before us 

 we find a description of structure founded mainly on 

 the author's own observations on certain types in each 

 class of the animal kingdom, and merely supplemented 

 by occasional references to the work of other authors. 

 Both methods have their value. That of Oppel tends to 

 produce a book which is a veritable storehouse of 

 information on the more limited subject with which it 

 deals, but it suffers from the disadvantage that such 

 a work must necessarily be enormously bulky and 

 proportionately slow in coming to completion, and as a 

 matter of fact Oppel's book, two or three volumes of 

 which have already been noticed in Nature, is not only 

 very far from that stage, but it would almost appear — from 

 the present rate of progress — that the end would never 

 be reached at all ; whereas in the work before us we have 

 an account of the minute structure of all classes of 

 animals which is, so far as it goes, complete, and is 

 not unduly large considering the vast extent of the 

 subject. 



As a matter of fact, Dr. Schneider's work is com- 

 pounded of three distinct parts, each of which might very 

 well have been published as a separate book. The first 

 of these — under the terms " Cytology" and "Organology" 

 — comprehends an account of the structure of the tissues 

 and organs of animals in general, the resemblances and 

 differences being duly noted ; it is, in fact, a general 

 minute anatomy of the animal kingdom. The third or 

 special part, which occupies by far the largest bulk, is also 

 purely histological, but the minute structure is dealt with 

 class by class, beginning with Porifera and ending with 

 Vertebrata. There is in this some unavoidable repetition 

 of the matter contained in the first part. On the other 

 hand, the second part — which is termed " Architektonik" 

 — is not histological at all, but morphological. It deals with 

 the forms of Metazoa and their mode of production, and 

 also includes the consideration of their classification, and 

 such questions as the formation of species and the causes 

 of variation. All this might very well have been omitted 

 NO. 1727, VOL. 67] 



in a work dealing with histology— that is to say, a know- 

 ledge of the subject might very well have been assumed 

 — in which case the bulk of the volume would have been 

 reduced to more manageable proportions. Moreover, it 

 could have been further reduced by a great diminution 

 of the bibliography, which, although extensive, merely 

 amounts to a collection of titles, for the papers given in 

 it are not specifically referred to in the text. The value 

 of such a list is not apparent, since at best it is sure to be 

 incomplete and could, in fact, be readily compiled more 

 efficiently from well-known publications accessible to every- 

 one. It will appeal to authors who do not take the trouble 

 to search out their own references or to verify them for 

 themselves, but adds no real scientific value to a work of 

 this sort unless the papers quoted have a direct bearing on 

 points treated in the book itself. There are always to be 

 found in the compilation of such lists sins both of omission 

 and of commission — papers of a trivial and unimportant 

 character included, and others of considerable importance 

 omitted altogether. A bibliography, to be of actual 

 value to the readers of a book, must not only have a general 

 relationship to the subject-matter of the work, but a direct 

 specific relationship to the detailed statements and 

 conclusions of the author. As examples of what biblio- 

 graphies in works on morphology should be like, those 

 given in Balfour's "Comparative Embryology" and in 

 Minot's " Human Embryology " may be instanced. With 

 such as these, which add a definite value to the works 

 which they complete, a bibliography like that in the work 

 under review, even although it contains 36 pages of titles, 

 contrasts unfavourably. In most other respects, Dr. 

 Schneider's book is to be commended as a creditable 

 attempt to supply a want which has been long felt, but 

 which, no doubt, the magnitude of the task has hitherto 

 deterred others from embarking upon. 



It should, however, be stated that the author's method 

 is dogmatic rather than critical, and that in disputed and 

 controversial questions he gives the views of the Vienna 

 school of histologists, to which he himself belongs, 

 without, as a rule, so much as hinting that other views are 

 held. If this is a fault, it is one which can be easily 

 forgiven to the author of a text-book, for at least it 

 tends to prevent a confusion of ideas on the part of the 

 learner, to diminish the bulk of the work, and generally to 

 present its contents in a more readable form, and one 

 more useful to the average student. 



PHILOSOPHY AND SCIENCE. 



The World and tin- Individual. First Series : The 

 Four Historical Conceptions of Being. By Josiah 

 Royce, Ph.D. Pp. xvi + 588. (New York : The 

 Macmillan Company; London: Macmillan and Co., 

 Ltd., 1900.) Price 12s. 6d. net. 



The World and the Individual. Second Series : Nature, 

 Man, and the Moral Order. By Josiah Royce, Ph.D. 

 Pp. xvii -j- 480. (New York : The Macmillan Com- 

 pany ; London : Macmillan and Co., Ltd., 1901.) Price 

 12s. 6d. net. 



IN the first series of these remarkable Gifford lectures, 

 Prof. Royce gives us the broad outlines of an ontology 

 which serves as the philosophical basis for the special 

 discussion of cosmological and ethical problems contained 



