SCIENTIFIC COMMITTEE, APRIL 24. 
XXXI 
Scientific Committee, April 24, 1900. 
Dr. Maxwell Masters in the Chair, and six members present. 
Ash-shoots barked by Hornets. — Mr. McLachlan exhibited growing 
shoots completely ringed by hornets. This is apparently a rare occur- 
rence, but the Chairman recorded a similar instance which had come 
under his notice in Messrs. Lee's nursery at Isleworth many years ago. 
Fasciated Boots of Aloe sp. — From Mr. Justus Corderoy came speci- 
mens of pot-bound Aloe-roots, some of which were markedly fasciated. 
Fasciation so common in stems is very rare in roots, only two or three 
instances being recorded, viz., in Spiraeas and in some epiphytal Orchids. 
Umbellate Primrose.— My. Arthur Sutton sent a flower of this variety, 
at one time confused with the Oxlip. 
Evolutio7i Committee. — Mr. Bateson, F.R.S., attended as a delegate 
from the Royal Society to bring before the members of the Committee 
some explanations of the kind of work which it was hoped some cultivators 
might be disposed to undertake, with a view to the accurate observation 
and, where possible, measurement of variations in the plants under their 
•care. A raiser of Chinese Primroses, for instance, might keep under ob- 
servation all the variations that arise, measure and draw or photograph 
them before throwing them away, so that we should have some record of 
the intermediate stages between the original forms and the variety 
thought worthy of perpetuation. 
Scientific Committee, May 8, 1900. 
Dr. M. T. Masters in the Chair, and six members present. 
Peach-trees diseased. — The following report was received from Dr. 
W. G. Smith upon the specimens received on March 26. He also observes 
that he is continuing the cultures of the fungi, as at present he is un- 
certain between Fruit-rot {Moiiilia fructigcna) and a form of Cladosporium. 
" The cause of discoloration of the bark of the twigs is evidently a fungus 
which can be found in these parts. The absence of good examples of 
reproductive organs renders identification uncertain. In the twigs the 
fungus has passed the winter, and made its way into the leaf-buds and 
flowers, causing the damage there. With a fungus such as this the 
course of treatment is summer spraying. Peach foliage is delicate, and 
the spraying solution must be dilute ; for example, Bordeaux Mixture 
made with not more than 2 lb. copper sulphate and 2 lb. quick-lime 
in each 50 gallons of water. The foliage should be thoroughly wetted 
with a fine spray, preferably that given with a sprayer like those supplied 
by Strawson and other firms. In winter pruning should be carried out, 
so as to remove all discoloured twigs. This treatment will probably 
require to be carried out for several seasons. The fungus might be 
identified if specimens of foliage were sent during the summer." 
Vine-leaves diseased. — With reference to those sent to a previous 
meeting, from Gunnersbury, Dr. Masters observed that no mites could 
•be detected by Mr. IMichael, who had carefully examined them ; and 
