128 THE ELEMENTS OF VEGETABLE HISTOLOGY 



A e 



PLATE 47. Fibrovascular Bundles. 



A. Collateral type, Bamboo stem. 1. Fibrous tissue. 2. Ducts. 3. Sieve. 



B. Collateral Bundle, arrangement of fibrovascular elements. 1. Xylem. 2. 

 Endodermis. 3. Phloem. 



C. Bicollateral Bundle, arrangement of fibrovascular elements. 1. Phloem. 

 2. Cambium. 3. Xylem. 4. Cambium. 5. Phloem. 



D. Open collateral type, Aconite tuber. 1. Bast fibers. 2. Sieve cells. 3. Cam- 

 bium. 4. Wood fibers. 5. Ducts. 6. Medullary ray. 



E. Open Collateral Bundle, arrangement of fibrovascular elements. 1. Phloem. 

 2. Cambium. 3. Xylem. 4. Medullary ray. 



