142 MORPHOLOGY OF ANGIOSPERMS 



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Bot. Gazette 32 : 325-331. pi. 13. 1901. 



57. ROSENBERG, O. Ueber die Pollenbildung von Zostera. Meddel. 



Stockholms Hogsk. Bot. Inst. pp. 21. 1901. 



58. GAGER, C. S. The Development of the Pollinium and Sperm Cells 



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59. GUIGNARD, L. La double fecondation chez les Solanees. Jour. 



Botanique 16: 14-5-167. figs. 45. 1902. 



60. CHEAUVEAUD, G. L. De la reproduction chez le dompte-venin. 



Diss. Paris. 1902. 



