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V%J *',*" ' V ' o % * o *\ o " - I . **ff$ 



; v:.;y; ; ;>;;.. 



FIG. 6. 



Section of the ovary of a marsupial (Perameles obesula), showing a fully- 

 developed corpus luteum. (From a section kindly lent by G.H. O'Donoghue. ) 



X 60. 



