SCIENTIFIC COMMITTEE. SEPTEMBER !. 



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i; As regards the individual seedlings, they conform to a very common 

 type of germination among monocotyledons. The radicle is pushed out 

 by the lengthening cotyledon and grows downwards to fix the plant in 

 the soil. The cotyledon also elongates, following the growth of the 

 radicle, but its coiled end remains in the seed to absorb the foodstuff. 

 The limiting line between base of cotyledonary sheath and the radicle is 

 very well marked ; the hypocotyl is suppressed. 



" The seeds apparently belong to the first type of bulbiform seed to 

 which I refer in my paper in the Society's Journal (xxvi. [1901], pp. 

 89-96), i.e. they are true seeds, the outer integument of which becomes 

 thick and fleshy after fertilisation." 



Apple-tree, Scorched. — A letter was read from Mr. Dowson relating to 

 the bark peeling from one side of young apple trees. The dead bark does 

 not peel off on the south side only, as it would do from sun -scorch, to 

 which the mischief has been attributed, but on the north side also. 

 Lightning was suggested as the probable source of injury, as no fungus 

 could be detected. 



Cucumber Scab (Cladosporium scabies, Cooke). — Dr. Cooke, V.M.H., 

 said : " Since reporting on Cucumber Scab, I have received examples in 

 an earlier stage from Hillingdon. In these the spots or scabs are not 

 blackened, but smaller and somewhat depressed, and of a grey colour, 

 and. velvety from the mould which covers them. Each spot has, in this 

 case, an amber-coloured tear, or exudation of gum, and in some cases two or 

 three from the same scab. This gummy matter is hardened, and can only 

 be partially dissolved with difficulty. In so far as I have been able to 

 ascertain hitherto, this is a purely gummy matter, without organisation. 

 No cells or sporules of any kind could be found. It suggests that the 

 earliest manifestation of disease may be an exudation of gum, and this 

 might be an effort of the plant to cast off the parasite by the formation of 

 a gummy matter at the point of irritation. Some of the spots, however, 

 exhibit no trace of gummy exudation, but in all cases the Cladosporium is 

 present." 



A close atmosphere is favourable to Cladosporium, while a current of 

 air is destructive. The above shows clearly that the blackness or con- 

 vexity of the cuticle is not an essential of the parasite. 



Peas. — Mr. Worsley showed specimens of late Peas rotting near the 

 base, while the foliage above turns brown and shrivels. This condition is 

 very common this autumn, and is probably due to the excessive moisture 

 at the root. 



Scientific Committee, September 1, 1903. 



Dr. Cooke, V.M.H., in the Chair, with six members present, and Mr. A. 



Gaut, visitor. 



Hippeastrum species. — Col. Tillotson sent flowers of a plant from 

 South America. The petals were of a pale clear green, passing into 

 primrose, the stamens and pistil bright pink, and protruding far beyond 

 the petals, which were almost closed at the apex of the flower. Though 

 not very attractive in colour, it was thought it might be useful to breed 

 from, on account of the great substance of the petals. 



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