REVIEW. 



A Text-Book of the Principles of Animal Histology. By Ulric Dahlgren, M. S. 

 and William A. Kepner, A. B. Cloth. Pp. xiii+515. Price, $3.75 net. New 

 York: The Macmillan Company, 1908. 



This work of more than 500 pages, containing nearly 500 illustrations 

 of which about 300 are original, has had such a flattering reception and 

 has been so favorably reviewed that it is unnecessary further to discuss its 

 value. The authors state that the book "is intended to be a work that 

 teaches general principles and teaches histology as a pure science and 

 for its own sake. It is believed that it will serve as a broad foundation 

 for future studies of morphology and embryology as well as for the 

 medical studies." This object is well fulfilled. Eich fields heretofore 

 untouched by any text-book, such as the tissues that produce electricity, 

 light, gases, etc., are opened, offering the results of original research work 

 on these subjects. 



The illustrations are not only largely original, but they explain the 

 text by their clearness and detail. Many of them are diagrammatic, 

 thus furnishing an ideal method of instruction without sacrificing reality. 

 In this way the structure of protoplasm is made plain, chromatin changes 

 become distinct, the amplification of body surface is illustrated, the 

 arrangements of muscles' cells is explained, the relation of absorptive 

 surface is indicated, and many other obscure points are made clear. A 

 bit of muscle fiber shows relaxation in the segment at one end and suc- 

 cessive stages of contraction in all the other segments, and this is only one 

 of many unusual illustrations. 



The comprehensive character of the work is made clear by the following 

 list of tissues, to each of which a chapter is devoted : 



Epithelium. Alimentary tissues. 



Supporting and connecting tissues. Ductless glands. 



Tissues of motion. Tissues of respiration. 



Electric tissues. Gas-secreting tissues. 



Tissues of light production. Excretory tissues. 



Tissues of heat production. Protective tissues. 



Circulatory tissues. Tissues of reproduction. 



Nerve tissues. Nidamental and erectile tissues. 



Pigment tissues. Nourishing membranes. 



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