





c 



Fig. 20. — Photomicrographs of biopsy specimens of breast from a single cas- 

 trated male rabbit. (From Anselmino, Herold, and Hoffmann, Zbl. Gyniikol., 

 S9» 963-69 [1935] ) .;?, After castration. B, After treatment for 25 days with oestro- 

 gen. Development of the ducts has taken place. C, After further treatment for 6 

 days with corpus luteum hormone. There is marked development of the alveoli. 

 D, After the administration of anterior pituitary extract (lactogenic hormone) for 

 5 days. Lactation is under way. 



