igo RESEARCHES ON FUNGI 



Some of the chief results of the investigations now to be described 

 in detail were communicated to a meeting of the Fifth International 

 Botanical Congress ^ on August 19, 1930, and were subsequently 

 pubhshed in an article in Nature ^ on November 1, 1930. 



Definition of the Terms Diploidisation and Diploidise. — It was 

 in the article in Nature, to which reference has just been made, that 

 the writer first introduced the word diploidisation to designate in 

 the Hymenomycetes the process by which a haploid cell is con- 

 verted into a diploid cell, or a haploid mycehum into a diploid 

 mycelium, by the formation of conjugate nuclei within the cell or 

 within the mycehum. Another new word also introduced there 

 was the verb to diploidise. A haploid mycelium of one sex may be 

 said to diploidise a haploid mycelium of opposite sex, or two haploid 

 mycelia of opposite sex may be said to diploidise one another. 



Coprinus lagopus. — The fungus employed for this investigation 

 was Coprinus lagopus (Figs. 107, 108, and 109). This species, as 

 conceived of by me, has been very fully described and illustrated 

 in Volume III of these Researches,^ and it has been used as material 

 for experiments on sex under this name by my pupils, Irene Mounce, 

 W. F. Hanna,^ Dorothy Newton, ^ H. J. Brodie,'^ and also by myself.^ 



1 A. H. R. Buller, " The Biological Significance of Conjugate Nuclei in the 

 Basidiomycetes," I'ifth International Botanical Congress held at Cambridge, 

 Section for Mycology and Plant Pathology, August 19, 1930. 



2 A. H. R. Buller, " The Biological Significance of Conjugate Nuclei in Coprinus 

 lagopus and other Hymenomycetes," Nature, vol. cxxvi, Nov. 1, 1930, pp. 68(>-689, 

 with seven diagrams. 



3 These Researches, vol. iii, 1924, pp. 299-327, Figs. 130-147. 



^ Irene Mounce, " Homothallism and the Production of Fruit-bodies by Mono- 

 sporous Mycelia in the Genus Coprinus," Trans. Brit. Myc. Soc, vol. vii, 1921, 

 pp. 198-217 ; also " Homothallism and Heterothallism in the Genus Coprinus," 

 ibid., 1922, pp. 256-269. 



5 W. F. Hanna, "The Problem of Sex in Coprinus lagopus," Annals of Botany, 

 vol. xxxix, 1925, pp. 431^57 ; also " Sexual Stability in Monosporous Mycelia of 

 Coprinus lagopus," ibid., vol. xlii, 1928, pp. 379-389. 



^ Dorothy Newton, " The Distribution of Spores of Diverse Sex in the Hymenium 

 of Coprinus lagopus,'" Annals of Botany, vol. xl, 1926, pp. 891-917. 



' H. J. Brodie. " The Oidia of Coprinus lagopus and their Relation with Insects." 

 To appear in the Annals of Botany, April, 1931. 



8 A. H.R. Buller, " Experiments on Sex in Mushrooms and Toadstools," Nature, 

 Dec. 6, 1924 ; also A. H. R. Buller and Dorothy Newton, " The Mating Method ot 

 Identification of a Coprinus growing on Germinating Seeds of Mangel and Sugar- 

 beet," Annals of Botany, vol. xli, 1927, pp. 663-670, 



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