JVo. 17 Three cells in anaphase from a culture of chick osteoblasts, stained by 

 May-Grunwald-Giemsa. Preparation by Dr VV. Jacobson and reproduced by 

 his kind permission. Between the daughter groups of chromosomes is a 'trail' 

 of basophilic material. X 1750 (reduction 3/4). 



JVo. 18 Mouse spleen cell in interphase, showing some chromoncmata visible 

 in the living state. X 4150 (reduction 3/4). 



