228 



tial lines, and in regular radial rows, having blind ends, as they seem to 

 start and to stop anywhere. The tangential rows branch, the branches 

 running into other rows or joining with the cells aromul trachete. Some- 

 times the tangential and radial rows are so regular that they give the 

 wood a cross-barred appearance. 



The medullary rays consist of very narrow, long cells, the long diam- 

 eter rmniing in a radial direction. They are from one to four cells wide, 

 the more common numlier being two. They are from al)out hfteen to 

 fifty cells in height, though an accurate count could not be made, due 

 to the presence in every ray of larger sclerenchymatous cells. One oi- 

 more of these sclerenchymatous cells, having fairly thicli walls, occur in 



Leopard-wood. Trans. Sect. ( x 300 > 



each ray, either at the end or throughout its height. In all 

 sclerenchyma cell occupies the place of two to four of the 

 parenchyma cells and seems to be the result of the merging of a 

 of the parenchyma cells. They are seen to best advantage in the 

 tial section. 



In a snnilar way the radial rows of parenchyma, though as 

 in their formation as the rays, are easily distinguislied from the 

 their greater size and sclerenchyma tons v.alls. 



cases a 

 I'egular 

 number 

 tangen- 



regular 

 ravs by 



