AUTHOR S ABSTRACT OF THIS PAPER ISSUED BY 

 THE BIBLIOGRAPHIC SERVICE, SEPTEMBER 29 



QUANTITATIVE STUDIES ON THE GROWTH OF THE 

 SKELETON OF THE ALBINO RAT 



HENRY H. DONALDSON 



WITH THE ASSISTANCE OF SARA B. CONROW 



The Wistar Institute of Anatomy and Biology 



TWENTY-THREE CHARTS 



INTRODUCTION 



In the following pages we shall describe several quantitative 

 growth changes in the skeleton of the albino rat between birth 

 and maturity. This investigation is a study of bones as part 

 of the entire mammalian body, and not of bone as a special 

 tissue, and this limitation of the problem explains the method of 

 procedure. 



For the 'ligamentous' skeleton of the albino rat we have the 

 data of Jackson and Lowrey ('12) based on seven age groups. 

 The skeleton, as prepared by these investigators, consisted of 

 the bones, plus the cartilages and ligaments, which remained after 

 the muscles had been rapidly dissected away fron these parts in 

 the fresh state. Their study dealt with the entire skeleton as 

 one of the tissue systems. It has seemed to us, however, desir- 

 able to study also the skeleton as represented by the bones alone, 

 because this would admit of dealing with the bones in detail, 

 and also would give material which sooner or later could be com- 

 pared with the corresponding material from man. 



It is the main purpose of this study, therefore, to furnish data 

 on the skeleton and its parts in albino rats of different body 

 weights and of different ages, presenting these data in such a form 

 that they can fairly be compared with any new set of values 

 taken from other rats examined by similar methods. 



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