October 19, 1906.] 



SCIENCE. 



497 



any characters by which they can be distin- 

 guished from, their next of kin. The differ- 

 ences are merely comparative and often in- 

 tangible, and the author kindly warns his read- 

 ers that they can not hope to satisfactorily 

 discriminate between them; and that when 

 certain groups ' are critically studied as a 

 whole,' as in the ease of Thomomys, a con- 

 siderable number of them * will probably be 

 dropped.' Under coyotes, of which three spe- 

 cies are credited to California, he says: 

 " Little harm would be done if all the Cali- 

 fornia coyotes were grouped together under 

 the name [Ganis'] ochroptbs. * * * Those not 

 experts will find it difficult to determine the 

 species of coyotes." 



Following the main text is a chapter on 

 'Life Areas in California' (pp. 283-291), 

 illustrated with a map, on which are indicated 

 the seventeen faunal divisions the author has 

 found it desirable to recognize. This is fol- 

 lowed by a ' List of California Mammals and 

 their Faunal Distribution,' which is noted by 

 means of references to the map. A glossary 

 and a very full index (40 pages) close the 

 volume. J. A. Allen. 



Physiology of the Nervous System. By J. 

 P. MoRAT, of the University of Lyons. Au- 

 thorized English edition, translated and 

 edited by H. W. Syers, M.A., M.D. 

 (Cantab.), Physician to the Great Northern 

 Central Hospital. With 263 illustrations 

 (66 in colors). Chicago, W. T. Keener & 

 Co. 1906. Pp. xxviii + 680. 

 This work, a portion of the * Treatise on 

 Physiology' by Professors Morat and Doyon, 

 is a full and systematic exposition of the 

 physiology of the nervous system. The sub- 

 ject has been treated with great clearness and 

 conciseness. The elementary nervous func- 

 tions, including the anatomy and functions 

 of the neuron in general, the methods of using 

 electricity in the study of nerve actions and 

 the effects of nerve poisons, are discussed in 

 the first part. The individuality of the neu- 

 ron is brought out as the essential point in 

 the theory of the nervous element without 

 entering into a technical discussion on the 



continuity or the contiguity of the articulated 

 prolongations of these neurons. With refer- 

 ence to the question of nervous amcebism, as 

 with other mooted points which at the present 

 time only lead to fruitless discussion, the 

 author takes a neutral stand. The laws of 

 Waller, in modified form, are described in a 

 clear manner. The views of Bethe, opposed 

 to the Wallerian idea of the regeneration of 

 the peripheral stump of the severed nerve, 

 are not discussed, perhaps, to the advantage 

 of the lucid presentation of the general laws 

 of nerve degeneration. Death by electricity 

 is discussed in the light of recent experiments 

 on animals and of accidents arising in in- 

 dustrial applications of high-tension electrical 

 currents. 



The systematic functions, *. e., the func- 

 tions which originate in the associations and 

 definite relationships which are established 

 between the cellular functions, are discussed 

 in the second part of this work. The rela- 

 tionships of sensation and motion are defined 

 very concisely. In introducing this impor- 

 tant chapter the author tersely says: 



Except for the infinitesimal part which each one 

 of us plays therein a knowledge of the living 

 world is based on anthropomorphic reasoning, and 

 it is impossible to base it on any other reasoning. 



Hence it is necessary to exert great prudence in 

 employing it. 



This part contains sub-chapters on the 

 metamerism of the spinal nerves; and their 

 functions, and the fundamental determina- 

 tions of the cranial nerves. The pneumo- 

 gastric and trigeminal nerves are very thor- 

 oughly treated. The chorda tympani is re- 

 garded, together with the two superficial 

 petrosal nerves, as the principal continuation 

 of the nerve of Wrisberg (nervus inter- 

 medins). In the second chapter the reflexes, 

 conscious, sub-conscious and unconscious, are 

 classified and described extensively. The au- 

 thor avoids attempting to explain the mechan- 

 ism of inhibition, but indicates by comparisons 

 how this phenomenon belongs to the category 

 of explicable facts of which the explanation 

 itself is wanting. 



The most noteworthy and interesting por- 



