CELLULOSE-PROTEIN COMPLEXES 



243 



Fig. 10. Electron micrograph of lamellae stripped from the wall of Chaefo- 

 morpha melagonium. Note: (1) The apparent "stray" microfibrils are in situ as 

 deposited because they are attached to a lamella at both ends. (2) One set of 

 microfibrils interweaves with the other. The run of the "strays" proves that this 

 interweaving is real and is not due to accidental stripping away of microfibrils. 

 Shadowed Pt. XI 7,000. 



microfibrils which are oriented at random. In the next one, deposited 

 to the inside of the first (Fig. 11), the microfibrils are oriented 

 transversely to an axis passing through the point of attachment to 

 the substrate. Microfibril synthesis and microfibril orientation seem, 

 therefore, to involve different mechanisms. The microfibrils of this 

 second lamella, which run in slow spirals round the sporeling, are 

 preceded by the development of coarse bands with similar orienta- 

 tion, which appear to be cytoplasmic (Fig. 11). Microfibrils de- 

 velop within these bands; they are first observed at a point on 

 what may be called the equator and appear to develop by end- 

 synthesis in such a way that they remain within the coarse bands. 

 In the third lamella, the microfibrils run from pole to pole of the 



