'' Fig. 7. Tail cores of T2 attached by 

 their fibers to a cell wall (Magnification 

 X 33,000). (From Kellenberger and 

 Sechaud, 1957.) 



Fid. S. 'I'2 particles after interaction 

 with a cell wall. Note the alterations 

 in the structure of the phage tail 

 (Magnification ■ 2G,(100). (From Kellen- 

 berger and Arber. 1955.) 



