CONTRIBUTIONS FROM THE WISLEY LABORATORY. 



365 



Gardeners' Chronicle of May 23, 1903: — "I have only this moment 

 read that Dr. M. 0. Cooke has stated in the Gardeners' Chronicle 

 (1903, p. 187) that I have identified the fungus in the warts of potatos 

 as Urcphlyctis leproides (Trab.), P. Magnus, which causes the beet- 

 root tumours ; but this is a mistake on the part of Dr. Cooke. I have 

 never seen the warty potatos, which I regret very much, and of 

 course I have written nothing about them. But the description given 

 by E.. ScHiLBERSZKY in Berichte der Deutschen Botanischen Gesell- 

 schaft, vol. xiv. (1896), pp. 36, 37; and the description and figures 

 given by Mr. M. C. Potter in the Journal of the Board of Agriculture, 

 vol. ix. December 1902, p. 320, plate iv., seem to me to show that 

 the fungus of the warty potato disease is entirely different from 

 Urophlyctis leproides (Trab.) in the beetroot tumours, and belongs 

 apparently to another genus, called by Schilberszky Chrysophlyctis, 

 with the species Chrys, endobiotica. I should be very glad to receive 

 material of the warty potato disease, in order that I may study it." 



Subsequently Magnus received potato material and was able to 

 confirm his view that the organism was not Urophlyctis leproides 

 . (Trabut), P. Magnus. Hence Urophlyctis or Oedomyces may be dis- 

 missed from further consideration here. During the time that Cooke 

 and Massee were occupied with this disease, W. Carruthers,^ Con- 

 sulting Botanist to the Eoyal Agricultural Society of England, had 

 received diseased potatos from J. 0. Bryner Jones, obtained from 

 a garden near Dolgelly. These potatos were handed to Miss Lorrain 

 Smith, v^ho reported that the diseased tissue contained an organism 

 belonging to the Chytridiaceae. This organism resembled very closely 

 Schilberszky's new Chytridiaceous fungus — Chrysophlyctis e-ndo- 

 biotica. Miss Lorrain Smith felt unable to definitely identify the 

 organism with Chrysophlyctis principally because two kinds of spore 

 had been described — resting- spores and swarm-spores; of these she 

 had observed only the former, and, moreover, the dimensions of the 

 spores were not given. Miss Lorrain Smith wrote to Schilberszky 

 in 1902 to ask him if he could identify the organism, but received no 

 reply to her letter. 



Carruthers' report for the year 1901-02 ended November 30, 

 1902. In a footnote he states that '* since the article was in print it 

 appears {Jour. Horticult., November 15, 1902, p. 454) that Dr. 

 M. C. CooKE sent specimens of what I believe to be the same disease 

 to Dr. Magnus of Berlin for identification." From this it would 

 > appear that the original report was ready before November 15 : that 

 J is, prior to the publication of the December number of the Journal of the 

 \Board of Agriculture. The report was finally published in the 

 Journal of the Royal Agricultural Society for 1902. It also appears 

 that an erroneous impression prevailed that Cooke himself had sent 

 specimens of the disease to Magnus for identification. 



The third view as to the identity of the fungus in the potato 



* W. Carrtjthers, Jour. Roy. Agr. Soc. Eng., Axiii. (1902), p. 292. 



