366 



MV GARDEN. 



of May in Devonshire, and in my garden at the beginning of June ; 

 it increased throughout the summer, and in September the trees were 

 in a terrible state. 



Our cabbages, cauh'flowers, shepherd's purse, and other similar plants, 

 are sometimes attacked with spots of white rust (Cystopus candidus, 

 fig. 8s i) on the leaves, arranged in a circular manner. The mycehum 



Resting spore. 



4^^+4-1 



Fig. 850. — Coleosponum pingue,- 

 iiat. size aiid magnified. 



Fig. 851. — Cystopus candidus, 

 nat. size and magniiied. 



Fig. 857 a. — CoprinUs atramentarius 



creeps through the cellular tissue of the plants, and after a time gives 

 rise to zoospores or moving bodies to perpetuate the species. I believe 

 that in all these cases the plant is previously pierced by an aphis. 



Our sweet-williams are frequently attacked on the upper surface of 

 the leaf with jet-black spots, which is a fungus called the Puccinia lyclt- 

 nidearztm (fig. 852). This species also attacks other species of Lychnis. 



Fig. 852.— Puccinia lychnidearum, 

 nat. size and magnified. 



Fig. 853.— Helmiiu..osporium 

 pyrorum (x 700 diam.). 



Fig. 854. — Siberian Crab 

 ■ Fungus (X 700 diam.). 



The fruit-trees are subject to the attack of a black fungus, of 

 which we note particularly two. species, one the Helminthosporium 

 tyrorum (fig 853), which attacks sometimes the Louise Bonne pear, 

 and very frequently the Easter Beurr6, causing the fruit to crack and 

 prematurely rot; so that really it is a very important fungus to be 



