PREFACE. 



IN the preparation of these pages the aim of the author has been 

 to present descriptions which should include the salient features of 

 the various structures with sufficient fulness to impress important 

 details without wearying minutiae : many years of teaching have con- 

 vincingly shown that too great conciseness of statement, on the one 

 hand, and too great elaboration of detail, on the other, are alike 

 unsatisfactory to the student in his efforts to gain an adequate and 

 lasting knowledge of minute anatomy. 



The recognition of the underlying morphological relations of the 

 tissues alone can bring the appreciation of the broad principles 

 requisite for the elevation of histology from a maze of barren details 

 to a study full of interest and suggestion. In order that these wider 

 bearings may become apparent, a brief account of the embryological 

 processes and the histological differentiation concerned in the de- 

 velopment of the tissues and the organs has been added to the 

 descriptions of the adult structures. The desirability of keeping the 

 size and scope of the volume within the limits adapted to its primary 

 purpose of text-book has forbidden the systematic consideration of 

 embryological data, and much of interest relating to the earlier 

 stages of development has been necessarily omitted. 



In adopting the character of the illustrations choice has been 

 influenced by the reflection that the mission of such drawings is 

 instruction, and that the illustrations best accomplishing that end 

 are of most value for the object at hand. With the exception of 

 those taken from other, duly acknowledged sources, the drawings 

 have been made by the author in nearly all cases with the aid of the 

 camera lucida or from photo-micrographs. While sufficiently dia- 

 grammatic to be efficient aids in the comprehension of the text, the 

 drawings are faithful likenesses of the original preparations; the 

 latter as far as possible have been taken from human tissues. 



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