4I 6 BOTANICAL GAZETTE [june 



6. Worsdell, W. C, Comparative anatomy of the Cycadaceae. Jour. Linn. 

 Soc. Lond. 33:439- 1898. 



7. Matte, Henri, Recherches sur l'appareil libero-ligneux des Cycadacees. 

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8. Bower, F. O., Comparative morphology of the leaf of the vascular cryptogams 

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10. Coulter, John M. and Chamberlain, C. J., Morphology of gymnosperms 

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11. Lyon, H., Embryogeny of Ginkgo. Minn. Bot. Studies. 1904. 



12. Livingston, B. E., Method for the measurement and control of soil moisture. 

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14. Chamberlain, C. J., Report on Dioon and Ceratozamia. Science 27:333. 



