Journal of Applied Microscopy. 517 



change from the nucleated corpuscle of the embryo to the blood cell of the adult. 

 All the steps of the process have not been observed, but the author believes that 

 a completion of his studies will show that the central or excentric body of Petrone, 

 found also by himself, is the remains of the nucleus of the embryonic blood cells. 



A. M. C. 



Peabody, James Edward, A. M. Laboratory I" this little book Mr. Peabody has 

 Exercises in Anatomy and Physiology. 79 attempted a thorough and logical ap- 

 ^^" " ^ •' 9 • plication of the laboratory method to 



the study of human physiology in the secondary schools, and has succeeded 

 admirably. As he remarks in the preface, " The following laboratory directions 

 aim primarily to familiarize the pupil with the working of his own organs of 

 motion, circulation, respiration, and digestion." 



The book opens with a chapter on " The Skeleton and Muscles." The 

 nature of the material used in much of the work is well illustrated in the first 

 section on the " Structure of Bones," where the material required is as follows : 

 " A clean rib of lamb or pork cut smoothly across the end ; two clean soup- 

 bones, one sectioned transversely, the other divided into halves lengthwise." 



In the section " Study of the Muscles " the pupil identifies, as far as possible, 

 the muscles of the arm and hand and their method of action. Then the structure 

 of muscle is studied from lean meat, then the structure and function of joints. 



The second chapter deals with " Foods," and here are given, in such man- 

 ner as to render their value clear to the student, the simpler tests for starch, 

 sugar, nitrogenous substances, etc. Following this is a chapter on " The Pro- 

 cesses of Digestion and Absorption," in which experiments upon the digestibil- 

 ity of the various nutrients are carried out and the principles of osmosis are 

 illustrated. Chapter IV deals with " The Blood and Circulation," and includes 

 work upon blood, a study of the mammalian heart, observation of the circula- 

 tion in the tail of the tadpole, and observations upon the student's own pulse. 



The other chapters of the book are as follows : " Oxidation and its Products," 

 " Respiration," " The Skin," " Excretion," " Nervous System," " Supplementary 

 Work." In conclusion are given " Rules for the Use of the Compound Micro- 

 scope," and "List of Apparatus and Chemicals for a Class of Twenty-four." 



Throughout the book the admirable plan is followed of limiting the material 

 for study as far as possible to common objects or substances which the student 

 knows as foods or has met with in some other way. 



Many interesting and valuable exercises are necessarily debarred from the 

 book in consequence of the fact that, as the author remarks, " physiology 

 unfortunately precedes physics and chemistry in the ordinary high-school 

 courses of study." Thus, the author has regarded it as necessary to omit any 

 thorough consideration of levers, and the senses of sight and hearing are left 

 entirely out of consideration, because of the necessity of some knowledge of 

 physics for any adequate understanding of them. Indeed, in this respect the 

 book illustrates clearly the disadvantages connected with this position of phys- 

 iology in the high-school curriculum. Physiology, even in its simplest form, 

 must be almost wholly an application of the principles of physics and chemistry. 



