JAPANESE SPECIES OF GYMNOSPORANGIUM* 



Frank D. Kern 



Pennsylvania State College 



Several years ago, while preparing an account of all the known 

 species of Gymno sporangium,^ the writer's attention was especially 

 attracted to the species reported from Japan. It did not seem at 

 all likely that the specimens and meager culture data then available 

 from that country adequately represented the genus as it probably 

 existed there. Since that time the publication of several new 

 species, based upon Japanese material, together with some addi- 

 tional culture data has materially added to our information. 

 Mycologists and plant pathologists in America also have an in- 

 terest in these forms because of the fact that they are likely to 

 be introduced into this country on nursery stock, such instances 

 having already occurred. - 



The best-known Japanese species is G. japonicum described by 

 Sydowin i899[Hedwigia38: i4i(Beibl.)]. This appears on gradual 

 fusiform enlargements of the stems of Juniperus chinensis. In 

 1900 M. Shirai reported successful cultures between this form and 

 Roestelia koreaensis on Pyrus sinensis (Zeitschr. Pflanzenkr. 10: i)- 

 The correctness of this cultural result has not been questioned 

 by the various writers who have had occasion to refer to it, 

 until the recent work of Ito (Tokyo Bot. Mag. 27: 221. 1913). 

 This investigator in May, 191 3, made cultures from a stem- 

 inhabiting form on Juniperus chinensis, which was without doubt 

 G. japonicum, on Pyrus sinensis, P. Malus, Amela?tchier asiatica, 

 and Pourthiaea villosa. If this were related to Roestelia koreaensis, 

 which was described on Pyrus sp., positive results should have 

 been expected upon one or both of the species of Pyrus, but such 



* Contributions from the Department of Botany, Pennsylvania State College, No. 7. 



1 Part II. A biologic and taxonomic study of the genus Gymnosporangiiim. Bull. 

 N. Y. Bot. Garden 7: 424-476. 191 1. 



2 Clinton, G. P. Ann. Rep. Conn. Agr. Exp. Sta. 1912: 350. 1913. Kern, F. D. 

 Log. cit., p. 461. Jackson, H. S. Jour, Agr. Research 5: 1003-1009. 1916. 



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