170 H. Tuciimann-Duplessis and L. Mercier-Parot 



nursing mothers considerably delays the somatic develop- 

 ment of the newborn and increases their mortality (Mercier- 

 Parot 1955). The course of the growth of the young rats 



Fig. 8. Growth curves of young rats nursed by mothers treated with cortisone 



after parturition. 



