SCIENTIFIC COMMITTEE, OCTOBER 10. 
clxvii 
SCIENTIFIC COMMITTEE. 
October 10. 
Dr. Hugo Muller, F.R.S., in the Chair, and two members present. 
Potatos tuith Scab. — A number of samples were received with the 
"description of the different manures suppUed. They were forwarded to 
Dr. Smith for examination and report. 
Fmigus on ChrysantJiemum Leaves. — Some leaves badly spotted with 
a brown fungus were received and forwarded to Dr. M. C. Cooke for further 
examination, who reports as follows : — " The Chrysanthemum disease is 
the ' rust,' which I refer to Uredo Hieracei ; but I cannot tell for certain 
until the Puccinia is found. I had it two or three years ago on leaves 
sent from Slough. It is capable of spreading, and I should destroy all 
the infected leaves by burning, if sprinkling with Condy's Fluid prove 
ineffective. It is better to sacrifice the entire plants than for it to 
establish itself as a permanent pest, like the Hollyhock disease (P. 
Malvaceanwi), to which it is allied. It is impossible to give the cause, 
but probably infection from other plants." 
Five-merous Eucharis.— A blossom of this plant, with itn whorls 
regularly arranged in series of fives — most unusual for a monocotyledon 
— was received from Mr. E. Escombe. An examination revealed the 
fact that it originated in the coherence of twin flowers. The stem, a 
short distance below the base of the inferior ovary, contained very 
numerous and scattered fibro-vascular cords. Nearer the flower they 
became thirty in number, and so entered the base of the twin ovaries. 
These were united by a common wall, in which two of the cords normal 
to the ovaries were suppressed. Hence the superficial cords were now 
reduced to ten only. This number, therefore, laid the foundation of the 
supply for the four whorls (perianth and stamens) of five parts each. 
Apart from the two united ovaries of three cells each, and six rows of 
ovules in each cell, no trace of the twin origin was visible. 
Chrysanthemum arrested. — Mr. E. H. Jenkins, of Hampton Hill, 
sent branches of the variety Madame Desgranges, in which the majority 
of the flowers were very small, with yellow petals on short stiff branches. 
There had been great difficulty in expansion from the bud. This was 
considered to be due to the excessive drought. The later flowers were 
nearly normal on slender pedicels. It was remarked that various kinds 
of Chrysanthemums had behaved in the same manner elsewhere, as well 
as other Composites, such as Rudbeckias. The cultural care had been 
quite correct, but while one plant was a failure, another in the same pot 
was normal. Such cases are not uncommon, some individuals succumb- 
ing to a disease ; while others, under the same conditions, may resist it. 
Mr. Jenkins asks if the form represents the original type. It does to 
some extent, being like the double form of the small C. indicum 
cultivated at the beginning of the century, and figured in the Trans- 
actiojis of the Royal Horticultural Society. It shows a tendency to 
arrest and reversion. The actual cause is obscure, but it would seem 
to be most probably climatal. 
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