xxviii PROCEEDINGS OF THE ROYAL HORTICULTURAL SOCIETY. 



its stalk lengthened, wrenching it away from the mycelium which gave it 

 origin, the water, &c, necessary for growth of the inverted mushroom 

 having been carried through the tissues of the one still attached to its 

 mycelium. 



" Canker " caused by Monilia. — Mr. Dunlop, of Armaghmore, sent 

 a branch of apple ' Lord Derby ' with cracked bark, giving it the 

 appearance of incipient canker. Inspection revealed the greyish sclerotia 

 of Monilia fructigena in the cracks, and Mr. Massee, V.M.H., said that 

 this fungus, which is perennial in the tissues, forms sclerotia beneath the 

 bark, causing the latter to be raised and to crack. Spores are formed on 

 these sclerotia, and the disease is spread to the young leaves, shoots, 

 flowers, and fruits by means of the spores. 



Begonia Bust, dc. — Mr. Curtis sent leaves of Begonia 1 Gloire de 

 Lorraine ' with rusty spots and markings on the leaves, due to the attack 

 of the Begonia mite. This pest is difficult to eradicate, but constant 

 vigilance and fumigation whenever necessary will usually keep it under. 

 A good wash for dipping plants attacked by mites is made by kneading 

 a handful of soft soap with a quantity of flowers of sulphur and dissolving 

 the whole in one and one-half gallons of water ; but even this, probably 

 the most deadly wash for mites, and at the same time harmless so far as 

 the plants are concerned, is not always efficient in killing the eggs of 

 the mite. 



Tuberous Solanums. — Mr. Sutton, V.M.H., read a paper on "Wild 

 Types and Species of Tuber-bearing Solanums," illustrated by lantern 



slides. 



He pointed out the peculiarities of the several tuber- producing species 

 of Solanum which he had secured and grown during the past twenty 

 years. Solanum Maglia, S. Jamesii, S. Fendleri, S. Commersonii, and 

 S. etuberosum were all illustrated and their cultural characteristics 

 commented upon. Experiments in hybridisation had been attempted, but 

 with no good results. In 1906 for the first time fruits of S. etuberosum 

 were discovered on one plant, and the seed gave rise to plants varying 

 considerably among themselves just as seedlings of the potato of commerce 

 vary. The fruit of this form is curiously spotted and the pollen is 

 elliptical in the one seedling examined, like that of the wild types and 

 unlike that of the cultivated. Mr. Sutton considers that this form is 

 possibly the wild type from which the cultivated potato has sprung, and 

 it is noteworthy that not once during the twenty years S. etuberosum has 

 been in cultivation at Heading has it been attacked by the potato disease 

 caused by Phytophthora iufestans. There would thus seem a possibility 

 of raising a race of potatos immune from the attacks of that disease by 

 cross-breeding with some of our common types. 



Fog Injury. — Mr. Hales showed shoots of various plants from Chelsea 

 showing injury through fog. 



