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scope. Directly under these spirals, and between them and the outward cuticle of 

 the plant, the oospores abounded ; there was no difficulty in procuring them, they 

 were unmistakable, and were as numerous, comparatively, as the Onion oospores 

 were scarce. I was glad to obtain these, having heard some years since that they 

 had only been found on Groundsel. On Groundsel I had found them with 

 comparative ease during the previous autumn, in a neglected potatoe bed. 



The oospores of Peronospora parasitica (Tul. ) I found in enormous numbers in 

 the decaying stumps of cabbages in my garden. Our friend, Mr. W. G. Smith, 

 sent me some turnips which were supposed to have them in great abundance, even 

 as he had himself found them. In those which reached me I could not find one, 

 although I spent some two or three hours at them. Knowing, however, that 

 Turnips and Cabbages were both of the Order Cruciferoe, I went to my cabbage 

 plants, and found on living cabbages sparingly scattered, in the conidial form, 

 the Peronospora, whilst on those whose heads were consumed for table, and whose 

 stumps remained in the ground and were rotting, the oospore was most abundant, 

 but nowhere except in the most putrid spots, which could be detected by a yellow 

 colour. That these were the vegetable resting spores seems to me settled, from 

 their exact correspondence with De Bary's figures, and also because I could not 

 detect on the living cabbages any other species of the order Mucedines. Their 

 locality corresponded very much with P. ganyliformis. 



Knowing that the Peronospora on the Ranunculus was to be had in several 

 spots, I watched very carefully for the oospores of it, and after several gatherings 

 of leaves infected with the acrospores, was fortunate enough to obtain some resting 

 spores, on the 29th of April. My suspicions of their being likely to be found on 

 the leaves of the Ranunculus itself were obtained from the fact, that a leaf of 

 some unknown plant had been sent to me the previous year full of resting spores ; 

 the leaf was very dead, dry, and brown. This leaf was a clue to my finding the 

 spores of Peronospora ficarice, for I took home with me, on the above date, some 

 decaying leaves, and on one or two of them the oospores were visible. One thing 

 was essential to their presence, namely, the decay of the stalk bearing the leaf. 

 Unless this were dying, and for a little distance downwards were brown from 

 death, not an oospore could be discovered. I anticipate, after realizing this fact, 

 that there will be no great difficulty in getting the resting spores of other plants 

 in a similar way. 



Mr. Phillips was fortunate enough lately to find Peronospora alta (Fckl.), for 

 the first time on record, I believe, in England. I had searched over and over 

 again unsuccessfully for it, and am satisfied that I have found plants infected with 

 it, but which, owing to the locality not being suitable for developing it, would 

 not grow it. This Peronospora grows on plantain, a plant which takes to itself 

 an unusual time in drying, as is known by its local title of " Jack set the rick on 

 fire," because the moisture in the leaf does not escape, and therefore ferments, and 

 ultimately, if very abundant, burns the rick. In one or two leaves sent to me 

 there are some very dark spots, which I feel sure contain the oospores ; as yet 

 they are not ripe enough to be seen under the microscope, I have little doubt 

 that they will be discovered there by and bye. 



