LONG and MARK- Maturation of Egg of Mouse 



Plate a 



A 



n»*H 



a b e d e f 



II I' i j /•• / 



A. Mouse Cage. (For description see p. 6.) 



B, C. Suspended mouse cages, with self-recording apparatus to indicate approximately the 



time of parturition of a gravid female. (See pp. 7-10.) 

 G. Chromosomes of first maturation spindle. (See pp. 28-30.) 



