864 



JOUENAL OF THE ROYAL HORTICULTQRAL SOCIETY. 



which causes beetroot tumour, and known as Oedomyces leproides 

 or Urophlyctis leproides. Although I did not find them, Mr. Mas see 

 informs me that the first-formed spores are subglobose, produced at 

 the apex of a hypha, which has a large vesicular swelling just below 

 the spore exactly as in beetroot disease." The disease was given the 

 name of /* potato tumour." A short account of this report was pub- 

 lished in the Gardeners' Chronicle of August 16.* This is the first 

 published record which I have been able to find of the occurrence 

 of Chrysophlyctis endobiotica in this country.! 



Mr. Chittenden has kindly allowed me to examine an herbarium 

 specimen, given to him by Cooke, of the diseased potato, and 

 there is no doubt that the organism present in the specimen is 

 identical with that known as Chrysophlyctis endobiotica. On Novem- 

 ber 4, Cooke| stated that more recently specimens had been sent 

 to Berlin, with the result that Magnus had not only confirmed 

 this affinity, but had demonstrated it to be the same species known as 

 Oedomyces leproides, Trabut, so that beetroot tumour and potato 

 tumour were caused by the same fungus. 



Following close upon these incidents came an article by 

 G. Massee§ in the Journal of the Board of Agriculture of December 

 1902. The disease is described under the name of "black scab," 

 and the organism is identified as Oedomyces leproides, Trabut. 

 Massee, moreover, figures a " spore " similar in every respect to that 

 characteristic of the genus Urophlyctis. 



Oedomyces leproides was discovered by Trabut in the tissue of beet- 

 root tumours, and described in 1894. This beetroot Oedomyces was 

 reviewed, among others, by Magnus, in his account of the genus 

 UrophlyctisW published in 1897, and was therein regarded as a typical 

 species of this genus. 



A further statement by OookeIi appears in the Gardeners' Chronicle 

 of March 21, 1903: — "At any rate, it is quite certain that Dr. 

 Magnus was acquainted with the beetroot tumour, and we are 

 assured that, upon his examination of specimens of this warty potato 

 disease sent to him from this cpuntry, he has pronounced it to be 

 identical with the * beetroot tumour.' " The words we -are assured are 

 important since they show that Cooke did not himself send specimens 

 to Magnus but relied upon information given him by some one 

 else. Cooke's statement called forth a letter from Magnus*^ to the 



* M. C. Cooke, Gard. Chron., xxxii. (1902), p. 124. 



t A postcard dated July 28, 1902 (postmark), is preserved among Dr. 

 Cooke's drawings in the Library of our Society, signed * G. M.', which probably 

 refers to these specimens : *' The fungus on potato is Chrysophlyctis endo- 

 biotica (ScHiLBERszKY, BcT. Deut. Gescll., p. 36, 1896). I have only seen it 

 as British from near Birkenhead last year, where it completely destroyed a 

 field of potatos." 



X M. C. Cooke, Jour. E.H.S., xxvii. (1902), p. cxcviii. 



§ G. Massee, Jour. Bd. Agr., ix. (1902), p. 307. 



II P. Magnus, Annals of Botany, xl. (1897), p. 87. 



^] M. C. Cooke, Gard. Chron., xxxiii. (1903), p. 187. 

 P. Magnus, Gard. Chron., xxxiii. (1903), p. 329. 



