4IO 



NATURE 



[August 30, 1900 



following comments intelligible. Firstly, the demon- 

 stration of an essential and fundamental point, viz. the 

 higher degree of blood-pressure in the area supplied by 

 the left common carotid artery, leaves a good deal in the 

 way of direct evidence to be desired : the most important 

 point urged in support being perhaps the comparatively 

 greater frequency of cerebral haemorrhage on the left 

 side. The author admits that, as regards the brain, the 

 confluence of the two vertebral arteries (to form the 

 basilar) equalises the conditions on the two sides so far 

 as the parts (medulla, pons, and posterior parts of hemi- 

 spheres) supplied by these are concerned, whereas the 

 equalising effect is not supposed to be felt in other parts 

 of the circle of Willis. We regret that we can find no 

 direct guidance on this point in Hill's important work on 

 the cerebral circulation. 



The arrangement of the great vessels springing from 

 the aortic arch is also a subject that admits of a good 

 deal of discussion in the present connection. 



With reference to the auditory nerve (p. i6), and the 

 greater sensibility of the auditory centre in the left hemi- 

 sphere, it may be mentioned that some support is afforded 

 to this view by the earlier date at which the auditory 

 fibres running up to the first temporal gyrus in the left 

 hemisphere acquire their medulla, and presumably attain 

 a fully functional state (Flechsig). In his observations on 

 the eye, the author is to be congratulated on having 

 devised new applications of routine clinical methods to 

 the elucidation of the questions with which he deals. As 

 regards actual differences in the dimensions of the eyes, 

 it is remarkable that no evidence on this subject is forth- 

 coming from the otherwise exhaustive work by L. Weiss 

 on the anatomy of the eye {Anatomische Hefle, Bd. viii. 

 1897). The recognition of non-pathological differences 

 in the size of the pupils is a point on which it is worth 

 while to insist ; moreover, the phenomenon will lose 

 little, if any, of its importance as a physical sign in the 

 early diagnosis of certain nervous diseases {e.g. general 

 paralysis of the insane). As regards the weights of the 

 hemispheres of the brain, it may be well to remark that 

 there appears to be a mis-quotation on p. 49, where the 

 weight of a left cerebral hemisphere is stated to be 218 gm., 

 and that of the corresponding right hemisphere 133 gm. 

 only ; at any rate, if there is not a mistake in quoting 

 Hamarberg's figures, the brain could hardly be regarded 

 as other than pathological, and consequently valueless in 

 this connection. But more important than this is the fact 

 that Braune's extensive weighings show that the difference 

 between the two hemispheres is quite negligible. At the 

 same time we may mention that, according to Bastian, 

 the specific gravity of the left hemisphere exceeds that 

 of the right. Finally, we do not feel inclined to agree 

 with the author in explaining instances of the exist- 

 ence of double personalities on the supposed presence 

 of equal blood-pressure in right and left common carotid 

 arteries. 



On the whole, we think that while the amount of 

 evidence in support of the author's main assumption 

 might well be increased, at the same time the clear 

 record of observations, and the deliberate discussion of 

 their significance, will render Dr. Lueddeckens' volume 

 of much interest to biologists. 



W. L. H. Duckworth. 



NO. 1609, VOL. 62J 



MODERN VIEWS ON THE CHARACTERS OF 

 THE CELLULAR ELEMENTS IN THE 

 BLOOD. 



Histology of the Blood : Normal and Pathological. By 

 P. Ehrlich and A. Lazarus. Edited and translated by 

 W. Myers, M..A, M.B., B.Sc. Pp. xiii + 216. (Cam- 

 bridge : At the University Press, 1900.) 



NOT much more than a year has elapsed since the first 

 part of "die Anaemie,"by Ehrlich and Lazarus, ap- 

 peared in Nothnagel's " System of Pathology and Thera- 

 peutics " ; but during that short time the work has taken a 

 foremost place among those dealing with the histology of 

 the blood. Perhaps the most striking feature of the book 

 is its originality, broad lines being laid down along which 

 future investigators may work, and no subject is taken up 

 without being enriched by some suggestive hypothesis 

 based on interesting observations made by Ehrlich him- 

 self or some of his pupils. Although comparatively a 

 small book, it may be said, without disparagement to the 

 many other works on hasmatology, to be the one to 

 which the term " epoch-making" may, without exaggera- 

 tion, be applied. It is only possible to refer shortly to 

 some of the most important subjects discussed in its pages. 

 Although it is undoubtedly with reference to the leuco- 

 cytes that the most important observations are made, 

 there are also points of great interest treated of in the 

 chapter dealing with the morphology of the erythrocytes. 

 This is especially the case with regard to the authors' 

 views on polychromatophilia as a sign of degeneration, 

 and on the method of transformation of megaloblasts to 

 megalocytes and normoblasts to normocytes. Not less 

 important are the paragraphs dealing with the megalo- 

 blastic type of the blood and marrow in pernicious 

 anaemia. But it is when the authors come to discuss the 

 normal and pathological histology of the white blood cor- 

 puscles that we find on every page observations that shed 

 light on points that have been long in obscurity. 



Although the authors belong to a comparatively small 

 school that believes in the absolutely distinct characters 

 of two types of white blood corpuscles, lymphocytes and 

 granular leucocytes, yet no one, whatever his own opinions 

 may be, can rise from a perusal of these pages without 

 granting that no stronger case could have been presented 

 in support of this view than the one placed before us 

 in this book. Perhaps it is mainly to Ehrlich and 

 Ribbert in Germany, and Muir in this country, that 

 we are indebted for the most powerful arguments 

 against the view that all leucocytes are developed from 

 the lymphocyte. The arguments presented in this book 

 in favour of the view that there are two great types of 

 white cells, are obtained from morphological, experimental, 

 pathological and clinical data. The morphological 

 characters of the different forms of white cells are first 

 described in a very lucid manner. There is an exceed- 

 ingly valuable contribution to our knowledge of the 

 functions of the spleen in Kurloff's work on the effects of 

 removal of that organ from guinea-pigs. The functions 

 of the lymph glands and bone marrow are described, and 

 additional evidence is given in favour of the two-fold type 

 of the white blood corpuscle. 



The chapter dealing with the demonstration of the cell 

 granules and their significance is, of course, one in which 

 Ehrlich, as a pioneer in this subject, naturally finds him- 



