20 



RESEARCHES ON FUNGI 



Botrytis allii with Neurospora crassa, 



Sclerotinia fructigena with Neurospora crassa (Fig. 9), 



Sclerotinia fructigena with Neurospora tetrasperma, 



Sclerotinia cinerea with Neurospora sitoj)hila, 



Sclerotinia cinerea with Neurospora crassa, 



Sclerotinia fructigena with Neurospora sitophila, 



Sclerotinia fructigena with Botrytis allii. 



Kohler found that the telemorphic 

 and zygotropic reactions observed 

 in the combinations of species just 

 given are similar to, but always 

 very much weaker than, the tele- 

 morphic and zygotropic reactions 

 which take place between two my- 

 celia of one and the same species. 

 In no combination of species was 

 it possible to observe the broad 

 plasma-fusions that are so character- 

 istically formed between mycelia of 

 a single species. If any such fusions 

 do occur, the fusion-canals must be 

 extremely small. 



In 1931, in the fourth volume 

 of these Researches, 1 I discussed 

 the functional value of fusion- 

 channels in connexion with sex and 

 social organisation in the Higher 

 Fungi. 



In 1931, Forsteneichner 2 and, 

 in 1932, Matsumoto, Yamamoto, 

 and Hirane 3 reported the results of hyphal-f usion studies made on 



Fig. 9. — Result of a mixed sowing of 

 conidia of Sclerotinia fructigena, 

 f, and Neurospora crassa, c. 

 The S. fructigena hyphae have 

 sent out fusion -branches toward 

 approaching germ-tubes of A". 

 crassa. The fusion - branches 

 and germ-tubes have come into 

 contact with one another but, 

 so far as can be seen, have not 

 fused with one another. From 

 Kohler's Zur Kenntnis der vege- 

 tativen Anastomosen der Pilze. 



1 These Researches, Vol. IV, pp. 152-186, 231-232, 243-245, 300-301. 



2 F. Forsteneichner, " Die Jugendkrankheiten der Baumwolle in der Tiirkei," 

 Phytopath. Zeitschr., Ill, 1931, pp. 367-419. Cited from Matsumoto. 



3 T. Matsumoto, W. Yamamoto, and S. Hirane, " Physiology and Parasitology 

 of the Fungi generally referred to as Hypochnus Sasakii Shirai : I. Differentiation 

 of the Strains by means of Hyphal Fusion and Culture in Differential Media," Journ. 

 Soc. Tropical Agriculture, Vol. IV, 1932, pp. 370-388. 



