The CEstral Cycle in the Non-pregnant Female Edtherian. 
164 
J. P. HILL AND CHAS. H. 0 DONOGHUE 
One of two conditions may then ensue. (1) The various organs may remain for a few days in a stage of 
comparative inactivity, hut almost immediately recommence the changes indicative of Pro-oestrus. This 
short interval is termed dioestrus, and the animal is said to he Polyoestrous. (2) The various organs may 
remain for a long time in a state of rest, this being the proper Anoestrus, and the animal is said to he 
Monoestrous. 
