84 THE ANATOMY OF WOODY PLANTS 



represented at c in our diagram. This condition is present in the 

 adult structure of the wood of Casuarina Fraseri, as is shown in 

 Fig. 58. The primitive aggregate condition persists, on the other 

 hand, in C. tondosa, as is shown in Fig. 59. 



FIG. 64. Diagrammatic representation of a twig of Picea canadensis. Explana- 

 tion in the text. 



In the longitudinal aspect of the diagram presented to the reader 

 are shown the vertical views of the three types of rays illustrated 

 horizontally in a, b, c. Fig. 630' shows the tangential topog- 

 raphy of an aggregate ray. The clustering of the masses of radial 



