December 2, 1920] 



NATURE 



433 



the other digits is frequently subject to increase, 

 Prof. Wood Jones accepts the former of the two 

 alternative explanations, and hazards the opinion 

 that the reduction has been brought about by the 

 fusion of the two terminal phalanges. If on this 

 matter he is not so logical as we could wish, we 

 are more content with him in certain of his other 

 explanations, and think the reasons he gives for 

 the fusion of the fourth and fifth carpalia and 

 tarsalia to form the unciform and cuboid, and 

 for the shifting of the axis of the foot from the 

 line of the third toe to that of the second, both 

 adequate and ingenious. We are inclined also 

 to accept his view of the fate of the os centrale, 

 although here, as in other parts of the book, we 

 think it would have been well if the evidence from 

 morphology had been supplemented with that 

 obtainable from embryology. The curious order 

 in which the bones of the hand ossify is a matter 

 upon which we should like to have had some 

 light, but, unfortunately, none is forthcoming. 



In the chapter on the extrinsic muscles of the 

 hand reference is made to the muscles of the foot, 

 and the extensor brevis digitorum and the peroneus 

 tertius are spoken of as derivable from a deep 

 extensor sheet, the slips to the four inner toes 

 passing down into the foot, while the slip to the 

 little toe remained in the leg as the peroneus 

 tertius. This is a view of the origin of these 

 muscles which is in direct opposition to those 

 of Ruge, Hryce, and Keith, for they have shown 

 that the extensor brevis digitorum, despite its 

 innervation, has entered the foot, not from above, 

 but from behind, passing under the external mal- 

 leolus, while the peroneus tertius has originated in 

 quite a different fashion — by segmentation of the 

 extensor longus digitorum. The matter is, of 

 < (jursi-, of almost purely morphological interest, 

 but we have ventured to refer to it because of the 

 interesting problem presented by the nerve- 

 fibres for the extensor brevis digitorum changing 

 from the musculo-cutaneous branch to the anterior 

 tibial branch of the external popliteal nerve. 



Perhaps the most original and valuable part of 

 the book is that dealing with muscles and their 

 action. Here we have the results of a singularly 

 close studv of the various muscles of the hand, 

 both in health and in disease, both after organic 

 lesions and after functional disturbances, results 

 which enable the author to furnish us with the 

 very useful classification of muscles into prime 

 movers, antagonistic, synergic, and fixation 

 inusries, according to the particular part they 

 play in different movements. We arc also given 

 the exact meaning of the phrase "at rest" as 

 applied to a limb or a muscle, and supplied 

 with a physiological explanation as to when and 



why the position of rest is attained. The dis- 

 tinction between a limb which is immobilised 

 or mechanically at rest and one naturally at 

 rest is clearly drawn. In the chapters dealing 

 with the nerves an interesting summary is given 

 of the most recent work of Head, Elliot Smith, 

 Kinnier Wilson, and other neurologists — a sum- 

 mary supplemented by many original observations 

 and speculations, as, for example, the particular 

 association of trophic effects with injury to the 

 median nerve, and the possibility that the Pacinian 

 corpuscles are part of the sympathetic sensory 

 system the fibres of which in the hand run mainly 

 in the median nerve. 



Altogether, the book is one which, in our 

 opinion, places its author in the front rank of 

 anatomists, and does more, we think, than any 

 book published in recent years to rehabilitate the 

 subject of anatomy, and restore it to its rightful 

 place as the most fundamental and pervasive 

 subject in the medical curriculum. W. W. 



Identification of Monosaccharides. 

 Anleitung zum Nachweis, sur Trennung und 

 Bestimmung der reinen und atts Glukosiden 

 usw. crhaltetien Monosaccharide und Aldehyd- 

 sduren. By Dr. A. W. van der Haar. Pp. 

 "vi + 345. (Berlin : Gebruder Borntraeger, 

 1920.) Price 64 marks. 



THROUGHOUT the development of organic 

 chemistry the glucosides have maintained, 

 amongst phytochemical products, a position of 

 interest primarily due to their connection with 

 sugars. Their attraction as materials for 

 chemical study is intrinsic also, because they 

 present alluring structural problems, and reveal 

 the power of sugar molecules to combine with a 

 great variety of other types — for example, in 

 amygdalin, myronic acid, indican, and salicin. 

 Furthermore, it is largely upon the production 

 and examination of artificial gluco.<^ides that our 

 present conception of glucose itself is based. 



The diagnosis of a natural glucosidc is com- 

 plete only when the carbohydrate component has 

 been identified, and chemists have long been con- 

 .scious of the ditliculties inherent to such an opera- 

 tion, especially when only small quantities of 

 material arc available. The purpose of the work 

 under review is to facilitate this procedure, .nul 

 the author has assembled in concise form the vast 

 collection of experimental observations which have 

 been accumulated in this field. Thus the volume 

 offers ample and valuable information to those 

 concerned in the identification of monosacch.irides. 



It is axiomatic that in such a treatise much 



