228 



The timber is light in weight, as well as in colour, and is suitable for indoor 

 work, the grain being straight and the figure plain. 



{b) Anatomy. 



The most notable feature in the transverse sections of secondary wood is the 

 unusually large niuuber of manganese compoiuid containing cells, which cells 

 throughout are probably larger in diameter than those of other species, as illus- 

 trated in Figure 147. 



The radial sections produced some interesting features, almost specific, i.e., 

 the walls of the prosenchymatous cells of the tracheids being covered with bordered 

 pits always in single rows, vide Figures 149, 150, the former giving the pits in focus, 

 the centres of which in this case have taken the stain, probably marking the torus 

 of the organ. Another character is also represented in Figure 149, i.e., the simple 

 pits of the medullary rays, which in this case have a circular orifice, and number 

 mostl\' four between the walls of each lumen, as distinct from the oblique slit of 

 C. calcarata. 



The medullar}' ra}'s have comparatively very long cells and present a compact 

 body, the walls of the upper and lower layers being as well defined as those of the 

 inner. They stain indigo with haematoxylin, and have, perhaps, the most strongly 

 defined walls of all the Callitris, are one cell in breadth, and two to six or more 

 high. 



It was thought that this species was in a measure related to C. calcarata, 

 but there are certain anatomical characters such as the circular orifice of the 

 simple pit,&c., that give, at least, one feature of differentiation in secondary wood 

 characters. 



Figure 147 is a view of a cross section of the timber multiplied eighty times, 

 taken with the autumnal growth in the centre running from left to right and 

 indicated by the narrow lumina of the tracheids, which, in this case, are found to 

 contain the manganese compound in both that period and also the vernal time, 

 as evidenced by the black spots in the picture. The black lines running from top 

 to bottom mark the cells of the medullary rays, also containing this substance. 

 Figure 148 is a tangential section of the timber but, mifortunately, not a clear 

 one, but, nevertheless, is reproduced to show that it is possible to obtain a 

 number of rays in which the manganese compound is not found. \\\ the radial 

 section, Figure 149, the pits of the bordered cells are focussed, and (lie rays show 

 that all the cells are uniform in character and have no marginal trachcidal cells, 

 whilst in Figure 150 the borders of the pits are focussed, and some good samples 

 of medullary rays are also illustrated. 



