DEVELOPMENT OF ARTICULATED LATICIFEROUS VESSELS. 153 



in the secondary cortex shortly after the cells are severed 

 from the cambial layer. 



2. The communication between vessels not in contact is 

 effected in two ways ; partly by means of cross rows of cells 

 which undergo fusion, and partly by means of inosculating 

 outgrowths, which form connecting canals, as in the Con- 

 jugatae. 



3. Even before the cross-walls are absorbed the cells are 

 distinguishable by their contents, and probably already 

 contain latex. 



In conclusion, I must express my hearty thanks to Prof. 

 Sachs for the constant aid which he has given me through- 

 out my work. 



