186 METHODS OF USING CULTURE MEDIA 



A. "Vicjnal tubes,'' of the style shown (Fig. 122), are 

 made from glass tubes of about 6 to 8 mm. outside diameter, 



Fig. 120.— Tank with raised lids, (Vaughan.) 



Fig. 121.— Tank with lids lowered. (Vaughan.) 

 Figs. 120 and 121. — Vaughan and Novy's mass culture apparatus. 



