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[Vol. 8 
pistillate flowers. The pollen tubes grow inside between the stigma papillae 
and pass through 4 to 6 cells of which the upper one is longest and thickest. 
On the stigmas of the staminate flowers such papillae are not formed, so 
that here no pollen grains are found. The wall of the ovary is penetrated 
by numerous vascular bundles with resin ducts which continue to the upper 
end of the pistil where the resin ducts terminate blindly with pointed ends. 
The development of the fruit, which terminates the life of the plant, 
has been taken up in another paper (19). 
LITERATURE CITED 
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6. Hall, H. M. A Yosemite flora, p. 151. San Francisco, 1912. 
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11. Jadin, F. Observations sur quelques Terebinthacees. Jour, de Bot. 7: 382-390. 1893. 
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1911. 
14. Leblois, A. Recherches sur I'origine et le developpement des canaux secreteurs et 
des poches secretrices. Ann. Sci. Nat. Bot. VII, 6: 247-330. 1887. 
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