All,-.. 1019.] THE COBEELATION TN THE DIFFERENTICATION. 



169 



Table IX. The rate ot" sex differentiation in the prothallia of 

 Blechnum hipponicum. 0.25 per cent Knop's solution. 



Figures in the blackets show percentages. 



Table X. Ditto. 0.5 per cent Knop's solution. 



Literature Cited. 



Coulter, J. M. (1914): The Evolution of Pex in Plants. Chicago, 1914. 



De Bary, a. (1878 ) : Uber apogame Fame und die Erscheinung der Apogamie im 



allgemeinen. Bot. Zeit. 36: 449, 1878. 

 Errera, L. (1904) : Conflits de pr^seance et excitations inhibitoires chez les v^g^taux. 



Bull, de la socidtd royale de botanique de Belgique. t. 42. Cited in Goebel: 



Einleitung in die experimentelle Morphologic der Pflanzen. 74, 1908. 

 Goebel, K. (1887) : Outlines of Classification and Special Morphology of Plant. Vol. 



II. 190. English translation, London, 1887. 

 He™, C. (1896): Untersuchungen iibcr Farnprothallion. Flora: 83: 329, 1896. 

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Prothallia. Ann. of Bot. 12: 2.51, 1898. 



