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XVII. p. 252) has observed a fungus causing the same reddish-brown 

 spots on twigs of roses and has also recorded similar cracks and 

 canker spots previous to 1905. He regarded the fungus he found on 

 these spots as a new species of the genus Coniothyrium, giving to it the 

 name Wernsdorffiae. In 1905 G. Kock (Sond. Zeitschr. d. landw. 

 Versnchsiccsen in Oestcrretch) dealt with the same disease as "arose 

 parasite new to Austria." He alluded to Laubert's description and name, 

 and there can be no doubt that the malady observed by him is the same 

 as described by Laubert and in the present paper. Kock thinks Laubert's 

 new name unnecessary, as the simple difference in the size of the spores 

 of this form and another of the same genus is not sufficient justifica- 

 tion for establishing a new species. He refers the fungus to Coniothyrium 

 Fiickelii Sacc. I quite agree with this view, and think that this latter 

 name is correct, as my own measurements of the spores in the Irish 

 specimens practically agreed with the size of the spores of Saccardo's 

 fungus. This fungus is rather common on twigs of various shrubs 

 and trees throughout Europe (Lindau, in Engler and Prantl, 

 Pflanzenfam. I. ** p. 364). It has been found, too, that it is only a 

 form of Leptosphaeria Coniothyrium Sacc, an ascomycetous fungus. 

 The latter form is frequent on dead twigs of Bnbus. It is interesting 

 to note that Leptoaphaeria thus inhabits a member of the rosaceous 

 group, and although I have no evidence, it is not at all unlikely that it 

 occurs on dead rose twigs too. 



A good original illustration of a cankered rose twig is found in 

 Kruget and Rorig, Krankh. d. Nutz und Zierpflanzen, p. 157, Stuttg. 

 1908, which proves the presence of the disease in Germany. Professors 

 Kriiger and Rorig adopt Laubert's name, but as the disease is new to this 

 country 1 have thought it necessary to go into its nomenclature at some 

 length and consider that ths fungus causing the parasitic Rose Canker 

 should be known by its first name Coniothyrium Fuckelii Sacc. 



From the mode of life of the genus to which this fungus belongs, 

 there can be little doubt that its entrance into the tissues of the rose must 

 be through some more or less minute wound in the bark. A growing 

 rose tree supplies a perfect example of a shrub inflicting injuries to its 

 own growing parts as well as to neighbouring plants. For when moved by 

 the wind the prickly branches frequently puncture or tear the epidermis 

 of the leaves and shoots. The small splits and punctures made in this 

 way can always be found on any growing rose tree. In the normal course 

 these very slight injuries will heal immediately, and will appear only as 

 more or less raised spots, but the unhealed wounds are readily taken posses- 

 sion of by certain fungi. 



Now taking for granted that from this cause or any other (insects, 

 birds, *vc.) small wounds result, the spores of the Coniothyrium readily 

 take possession of them and germinate, sending out small mycelial tubes 

 which push their way beneath the bark, where the mycelium ramifies and 

 quickly permeates the tissues around the place of entrance, absorbing 

 the foi d necissary for its growth from the cell contents of the host. 

 The cells attacked die and the outward sign of the dead cells is seen in the 

 discol rati' n of the epidermal tissues, giving rise to the reddish-brown 

 spots on the bark of the affected shoot. In the course of its growth the 



