324 
T. G. Hill and E. de Fraine , 
branch, small portions becoming more or less detached from the 
flanks of the central bundle. This separation, however, when it 
does take place, is merely local; in no case have two distinct bundles 
been seen. 
Fig. 5. P. lanceolata. Transverse section of cotyledon shewing details of 
structure of the vascular bundle ; c., chlorenchyma ; ph., phloem; t.t., trans¬ 
fusion tracheides; x., xylem. The transfusion tracheides are particularly 
abundant on the right flank, x 280. 
Fig. 6. P. lanceolata. Longitudinal section of a cotyledon, shewing the 
transfusion tracheides reaching almost to the tip. x 200. 
