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FUNGI PARASITIC ON VACCINIUM VITIS-ID.EA. 

 By W. T. Thiselton Dyek, B.A., B.Sc. 



Certain gall-like bodies occurring on Rhododendron ferrngineum, as to 

 the origin of which opinions are somewhat divided, have recently been 

 the subject of some discussion in the pages of the 'Gardener's Chronicle.' 

 In the number for August 5, tlie Eev. M. J. Berkeley remarks in reference 

 to them, " Mr. Broome has recently sent from Perthshire a thinner but 

 similar substance on Vaccbiinm Fitis-Idma covered with a similar bloom. 

 There is no reason to suppose this is an insect product." 



About the mi(hlle of the same month I met with plants of Facclni/im 

 FUis-Idcea, affected in the way described near the Trossachs, and therefore 

 in the same county in which Mr. Broome also met with it. I submitted 

 a specimen to Mr. Berkeley, who informed me that it was the result of 

 " some species of Ancomyces, probably the same which accompanies or 

 causes the gall-like bodies on Rhododendron ferrugbieum.'''' These he had 

 already attributed (Gard. Chron., July 22, p. 944) to an Ascomyces, simi- 

 lar to that {A. deformans, Berk.) which produces blister in Peach-trees. 



Happening to show a Vncclnlnm aft'ected in this way to Dr. Ascherson, 

 of Berlin, he at once identified it as the effect of a fungus, Exobasidium 

 Vacrinii, Woronin, and informed me that it was frequently met with in 

 Germany. In Rabetdiorst's ' Fungi Europeei,' there are authentic speci- 

 mens from AVoronin, gathered near St. Petersburg. The fungus was, 

 however, originally described by Fuckel in the ' Botanische Zeitung ' 

 for 1861, p. 251, and he figures (tab. x. t. 7) a portion of the affected 

 Vacclniimi, and also the spores. He gave it the name of Fiisidiiim Vac- 

 cirtu, and published specimens with that name in his ' Fungi Khenani ' 

 (n. 221). I learn from Mr. Cooke that the same plant was collected a 

 quarter of a century ago by Dr. Greville, and named in MS. Gylindrosporium 

 deformans, but not described. In 1867, however, Woronin published an ela- 

 borate paper, illustrated with beautiful plates, contained in the fourth volume 

 of the ' Berichte iiber die Verhaudlungen der Naturforschenden GescUschaft 

 zu Freiburg im Breissgau,' (pp. 397-416, t. v. vi. vii.) in which 

 he states (p. 400) that while entirely agreeing with Fuckel that the dis- 

 eased state of the Vaccinium is produced by a parasitic fungus, and not 

 through the punctures of insects, he considers the fungus to be alto- 

 gether different from a true Fusidium. He also remarks that while 

 Fuckel had met with the fungus on both Facciniam Fitis-Idaa and F. 

 Myrtillns, he has only succeeded in finding it on the first of these plants. 

 Woronin represents in his figures the fungus as attacking, besides the 

 leaves, the twigs (f. 11, 12, 13), and also the fiowers (f. 16, 17, 18). The 

 parts aft'ected become much hypertrophied, of a pinkish-white colour, and 

 with a fiocculeut-looking surface. In a microscopic examination of a 

 section, the intervals between the cells are seen to be densely filled with a 

 mycelium from which clavate cells (dasidia) are protruded throiigh the epi- 

 dermal layer of the part of the plant aflPected. These basidia bear the spores 

 on short stalks. As remarked by Woronin (1. c. p. 412) Exobasidium must 

 necessarily be included amongst the Hymenomycetes. " It stands in the 

 same relation to the Hymenomycetes {Basidiomycetes) as the genus Exo- 

 ascus \_Ascomyces'\ to the Dlscomycetes (Ascomycetes).* Fuckel only 



* There is an abstract of Woronin's paper in ' Hedwigia,' 1867, pp. 150, 1.51. 



t Fusidium tumescens, Fckl. 1. c. p. 371, Fungi Rh. 1653, which also occurs on 



Vaccinium Vitis-Idcea, may pos&ibly belong to CaUjplospora Gwppertiana, Kiilm. 



