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author’s abstract of this paper issued Reprinted from The American Journal of 
by the bibliographic service, February 10 Anatomy, Vol. 31, No. 4, March, 1923 
DEVELOPMENT OF THE METANEPHRIC ANLAGE 
OF CHICK IN ALLANTOIC GRAFTS 
RUTH RAND ATTERBURY 
Department of Anatomy, Columbia University 
FIVE TEXT FIGURES AND THREE PLATES (SEVEN FIGURES) 
CONTENTS 
Introduction. 409 
Material and method. 413 
Observations. 414 
A. Structure of the metanephric anlage at the time of grafting. 414 
B. Growth of the metanephric grafts in the allantois. 416 
1. Growth of the ureteric epithelium. 416 
2. Growth and differentiation of the nephric epithelium. 419 
3. Development of the stroma. 425 
Conclusions and discussion. 427 
INTRODUCTION 
The kidney is a structure peculiarly adapted for a study of 
the much-discussed problems of cell potentialities and cell 
differentiation and frequently has been used by investigators 
for this purpose. As is known the anlage of the permanent 
kidney is twofold consisting of, 1) the ureter bud, which gives 
rise to the collecting apparatus of the definitive kidney, and, 
2) the metanephrogenic cord, a strand of apparently uniform 
mesenchymal tissue into which the ureter bud grows. 
The cells of the metanephrogenic cord are mesodermic in 
origin. They arise from the primitive segment stalks of the 
two or three most caudal somites, which lose their metameric 
arrangement, fusing together into a continuous nephrogenic 
strand or cord. In the course of its development, the metaneph¬ 
rogenic cord takes two distinct lines of differentiation. On the 
one hand it is transformed into the highly differentiated secretory 
epithelium of the renal tubules, while on the other hand it gives 
rise to the connective-tissue capsule and stroma of the kidney. 
409 
