i8 9 6. SOME NEW BOOKS. 415 



The author introduces a new law under the name of Eutropy, 

 with the following signification : — In a series of analogous compounds, 

 each of which contains a different element taken from the same 

 horizontal line (in Mendeleef's series), while they are all alike in 

 other respects, their crystals constitute a similar series in which all 

 the crystallographic properties alter in a regular manner with the 

 increase or decrease of the atomic weight of the characteristic 

 element. This statement has been recently elaborated by Professor 

 Linck and one of his pupils in Ostwald's Zeitschvift, but seems scarcely 

 yet established on a sufficiently wide basis to be given as a general 

 law in an elementary text-book. It is simply an extension of the 

 accurate work recently done on the sulphates by Mr. A. E. Tutton. 



We have pointed out various shortcomings of this book in the 

 interests of the readers for whom it is intended, but must in justice 

 add that in the matter of information it is remarkably complete and 

 well suited for more advanced students. The classification of twin- 

 crystals on p. 24 seems both logical and lucid. A word of praise is 

 due to the figures, and especially the coloured plates, which are 

 excellent ; but when all is said the question remains — Why are not 

 elementary text-books on Crystallography more readable ? 



Man and his Ancestors. 



The Structure of Man : an Index to his Past History. By Dr. R. Wiedersheim ; 

 translated by H. & M. Bernard, with a preface by Professor Howes. Pp. xxi., 

 227, with 105 figs. London: Macmillan & Co., 1895. Price 8s. 



Professor Howes has, we think, been well advised in securing the 

 competent assistance of Mr. and Mrs. Bernard in placing this highly 

 interesting work in the way of those anatomists who are unable to 

 read German. He has done a further service to those readers in 

 adding a few notes on his own account ; these notes are placed in 

 square brackets, and are deftly woven into the text, so deftly that no 

 one, were it not for the brackets, would have the remotest idea where 

 Professor Wiedersheim left off and Professor Howes began. The 

 book is practically a resume of vestigial structures in man, and of 

 certain rare reversions to what has been thought to be an ancestral 

 condition. Thus, hairy men and women, supernumerary mammae, 

 and such like monstrosities occur in abundance, while the inferiority 

 of the negroes, and particularly of the Veddas, is duly emphasised by 

 the damning frequency of the occurrence of ape-like characteristics. 

 Sometimes perhaps both the author and his editor become un- 

 necessarily discursive. We have wearied for a considerable period 

 of the pineal eye ; and why, seeing that " the pineal gland of Anthro- 

 poids is identical in appearance with that of man," should we have 

 three or four pages, illustrated, upon its general characters in reptiles 

 and fishes ? The glossary, too, appears to us to be a work of superero- 

 gation as an appendix to a book written for persons who presumably 

 have some acquaintance with the general facts of anatomy. But as 

 both the author and his editor are professors, they may have a lower 

 and possibly more correct opinion of the knowledge possessed by 

 those whom they address. Still, every student of anatomy must surely 

 have heard of histology, of anatomy, and even of biology ; definitions 

 in five words would seem unnecessary — though, to be sure, we have heard 

 of a candidate for a lectureship at a medical school who was perfectly 

 aware of what was meant by Zoology and Botany, but could not 

 understand what the advertisement meant by requiring a lecturer 

 upon Biology. 



