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of the Embryo of Indian Corn 315 



rangement of the main bundles, and in this respect rather resemble 

 the bundles given off to the secondary roots. 4. The first inter- 

 node closely resembles the root in structure. The peculiar ar- 

 rangement of the bundles may be in some way related to the fail- 

 ure of the first internode to attain a diameter greater than that of 

 the primary root. 5. The fibro-vascular bundles change from the 

 radial type to the collateral type in the second node. These bun- 

 dles on entering the second node pass outward and terminate 

 blindly toward the periphery, the last elements to disappear being 

 the xylem elements. 6. The bundles, of the sheath differ from 

 those of normal leaves in that they originate in the node from 

 which they are given off, that they blend into pairs and finally in 

 the sheath appear as two bundles at opposite points on the axis, 

 and that the curves of this bundle in the node are very sharp. 

 Cornell University, 



Explanation of i»late 342. 



1. Longitudinal section of root-tip. 2. Cross-section of root. 3. Cross- section 

 °f first internode. Ep. Epidermis. C. Cortex. Pc. Procambium. B. Pseudo- ves- 

 sels. C.C. Plerome. R. Root-cap. En. Endodermis. Pe. Pericycle. Xy. Xylem. 

 S. Secondary root. K. Lame vessels. PL Phloem. 



