68 J. W. REED ON UROMYCES PISI. 



were instrumental in propagating the blight on the wheat ; 

 and an author, writing in 1781, and quoted by Mr. Plowright, 

 says that he found by actual observation that the barberries had 

 been widely removed from the hedges of Norfolk. As might 

 have been expected, many wild and fantastic suggestions were 

 made as to this hypothetical relation of the barberry to the 

 mildewed corn-fields. At length, however, in 1816, the true 

 connection was demonstrated by a Danish schoolmaster, who 

 rubbed the underside of a barberry leaf, infected with ^cidia, on 

 to some plants in a field of rye, so that some of the ^cidiospores 

 were left on them. The rye plants thus treated were marked 

 by being tied to sticks. In a few days the fungus had spread 

 itself widely over the plants in question, whilst all others in the 

 field were free from disease. It may be mentioned here that 

 to-day, in the Swiss Alps, the precautionary removal of the 

 barberry bushes is too much neglected, to the great detriment of 

 the wheat-fields. 



Mr. Plowright, in his delightful Monograph on the " British 

 Uredinese and Ustilaginese," which is well worth the attention of 

 3 very member of this Society, says : " In 1861, De Bary showed 

 that many of the Uredinese not only had uredospores and teleuto- 

 spores, but also that the latter gave rise in many cases (but 

 not in all) to secidiospores, and conversely the pecidiospores to 

 uredospores. ..." 



(These several forms of spores will be more particularly dealt 

 with later on.) 



" It further occurred to him that, as there were several secidia 

 unaccompanied on the host -plants by any other spore form, these 

 might belong to Uredines which passed a part of their life upon 

 one plant and the remainder upon another." This supposition 

 Professor De Bary demonstrated to be correct in 1864. 



The real relations of Uromyces j^isi and what was up to then 

 known as " ^cidium cyparissise " were worked out by Schroter, 

 in 1875. Schroter was the first to produce the secidial stage on 

 our Euphorbia from Uromyces pisi. 



Mr. Massee, whose paper on the ''Evolution of the Basidio- 

 mycetes," recently read before this society, will long be remembered 

 with pleasure and profit, has been good enough to examine my 

 specimens, and has favoured me with the following notes for 

 inclusion in this communication : — 



