OF LOWER GREENLAND PLANTS. 



31 



Towards the edge of the pith the colls are large and compara- 

 tively thin-walled (see p., text-fig. 9). 



The vascular tissue is a hollow cylindrical monostfile. The 

 primary .vi/lem is much broken up into small groups of elements, 

 and these form isolated little clusters, separated by large ray and 



A. 



B. 



Text-fig. 8. BennetLitcs Gibsoniantts, Can*. A. Trunk cut across. 

 15. Cut tangentially to show coues and leaf-bases. After Carruihers. 



medullary cells (see pa;., text-fig. 9). These elements have very 

 thick walls and are irregularly scattered. The secondary wood, 

 forming a definite ring, is also of a very loose texture, the rays 

 between the radial series of trachcids being both large and 



