470 NATURAL SCIENCE. August. 



dealing with the nervous system lie claims unhesitatingly " the origin 

 of the vertebrate brain and spinal cord as the outcome of the nervous 

 system of the Arthropoda " ; the space devoted to these remarks 

 might well have been occupied by more precise descriptions of the 

 Arthropod nervous systems, and some attempt to explain to the 

 student the difference between the archicerebrum and syncerebrum, 

 neither of which terms are as much as mentioned. The omission 

 of any reference to the nervous nature of the radial cords in the 

 Crinoids is also unfortunate; the eight pages devoted to the nervous 

 system of the Echinodermata well illustrate the casual nature of 

 the author's method, for with the exception of a few remarks about 

 the eyes of the Starfish, the whole section is restricted to the one 

 type Echinus, while the other classes are quite neglected. Extracts 

 of great and unnecessary length are made throughout the book, but 

 it seems difficult to see on what principle the author has made his 

 selections. We should imagine he had bought up a job lot of Mr. 

 Romanes' pamphlets and incorporated most of them. Probably the 

 most serious omission is that there is absolutely no reference to the 

 phagocytes, and this alone would be quite sufficient to condemn 

 any book on Invertebrate Physiology. 



Life in Motion. By J. G. McKendrick, M.D., &c. London : A. and C. Black, 1892. 



Professor AIgKendrick's book (of 200 pages) is written in a pleasant 

 and popular style, such as we might fairly expect from the author. 

 His lectures at the Royal Institution, substantially reproduced in this 

 little book — as, indeed, the occasionally interspersed " my young 

 friends " reminds us — were probably even more interesting than the 

 report of them before us. Some of the effect of the subject is lost, for 

 apparatus is much less convincing in pictures than when seen in 

 action. With the exception, however, of the phrase quoted above, 

 and repeated more than once, the book is not written in lecture form, 

 and is all the better for that. " The delivery of the lectures," says 

 Dr. McKendrick, " was a pleasure to myself" ; and he expresses the 

 hope that, when in print, they will interest not only the young, but 

 " even those who may feel that they are no longer young." We 

 ourselves are in the sere leaf and belong to the latter category, and 

 we have undoubtedly been most interested in reading the work. 

 Its object is to give an idea of the principal facts in muscle physiology; 

 the title, therefore, is a little misleading, as there is no account of 

 ciliary movements. Though professedly written for young persons of 

 all ages, we notice an occasional lapse into unexplained technicalities; 

 thus, on page 163, the author speaks of an instrument which has a 

 resistance of 86,000 ohms, an expression which can hardly have been 

 understanded of the people. Besides the illustrations of apparatus 

 there are numerous cuts, illustrating other points; diagrams, for 

 example, are given of the musculature of the human arm and the 

 frog's leg; apropos of the arm muscles. Dr. McKendrick intimatesthat 

 young ladies, although they possess a biceps, are not so much 

 interested in its welfare ; in these days of lawn tennis, of lady 

 champions, and of Girton College, we are disposed to think that the 

 biceps is greatly in favour with the other sex. On page 79 is a repro- 

 duction of a tracing of the muscle curves, obtained during the writing 

 of a sentence, which illustrate the innumerable contractions necessary 

 to make up what appears to be a single effort on the part of the 

 muscles; the curiously shaky result which is thus produced is indeed 



