ISOLATION AND PROPERTIES OF WALLS 



pyrenoidosa with dilute solutions o£ sodium hydroxide a 

 microfibrillar layer is revealed, and again the fibers lie at 

 approximately 90° to one another (Fig. 2). 



The presence of microfibrils in fungal cell walls has been 

 reported by several investigators (Frey-Wyssling and Miihle- 

 thaler,^^ Roelofsen,^! Shatkin and Tatum ^^). Roelofsen ^^ 

 found that the fibrils on the outer and inner layers of the 



li: 



(«) 



(P) 



Fig. 2. Electron micrographs showing microfibrillar structure in the 

 wall of Chlorella pyrenoidosa. (a) Walls treated with 0.5% NaOH for 

 30 minutes at room temperature (x 21,000). (fo) Walls treated with 

 3% NaOH for 30 minutes at room temperature (x 39,000). By courtesy 

 of Drs. Northcote, Goulding, and Home (Ref. 29). 



