Xll THE MOLECULAR ARCHITECTURE OF PLANT CELL WALLS 



PLATE VII facing page 



Fig. L X-ray diagrams of late wood from one transverse slice of 



a trunk of Pseudotsuga taxifolia 128 



Fig. 2. X-ray diagram of wood of Juniperus virginiana, beam per- 

 pendicular to grain 129 



Fig. 3. X-ray diagram of a sample oi Finns sylvestris, late wood, 



4th annual ring 129 



Fig. 4. X-ray diagram of a sample of Abies sp., 10th annual ring, 



late wood 129 



PLATE VIII 



Fig. 1 . X-ray diagram of immature sisal fibres (outer layer only 



of secondary wall) 160 



Fig. 2. X-ray diagram of mature sisal fibres (outer and inner layers 



both present) 160 



Fig. 3. Transverse section ofbamboo fibres between crossed Nicols 160 



Fig. 4. Enlargement of an X-ray microphotograph of the (single) 



wall of a vessel element of Quercus (oak) 160 



PLATE IX 



Fig. 1. Sector diagram of Coir before and after delignification 161 



Fig. 2. X-ray diagram of a block consisting of parallel strips of 



cambial tissues 161 



Fig. 3. As in Fig. 2, but beam parallel to the flat surfaces and 



perpendicular to cell length 161 



