XCviii PROCEEDINGS OF THE EOYAL HORTICULTUEAL SOCIETY. 
in America as a result, and not a cause ; that it follows upon some lesion 
in the foliage, as by punctures, &c., by insects. The same observation 
might apply to the presence of the Puccinia. No remedy could be 
suggested. It is best to destroy the plants entirely. 
Scientific Committee, July 25, 1899. 
Dr. M. T. Masters, F.E.S., in the Chair, and four members present. 
A Monstrous Begonia. — Mrs. G. Soames, of Welton House, Daventry, 
sent a peculiar blossom, with white petals and a large tuft of stigmas, 
apparently a male flower, with the stamens stigmatiferous. Dr. Masters 
undertook to examine it further and report upon it. 
A Proliferous Helenmm autumnale. — Mr. Veitch sent specimens of 
this peculiarity in w^hich the heads had given rise to pedicillate smaller 
ones, the corollas being more or less virescent as well. It is remarkable 
that this species is peculiarly liable to this malformation. 
Grapes loith Mildeiv — Cypripediums and Apple-trees Diseased. — The 
three following communications, on specimens sent to a previous meeting, 
were received from Dr. W. G. Smith, of the Yorkshire College, Leeds* 
A special and unanimous vote of thanks was rendered to him for his- 
valuable reports. Grapes with Mildew. — " The mildew is undoubtedly 
caused by the fungus O'idium Tuckeri, so well known in this country as 
the common Grape mildew. On treating the Grapes and leaves sent in 
various ways, the mildew continued to spread on the fruits, but never 
appeared on the leaves, which on receipt were very healthy. This 
supports Mr. Wright's opinion. Most of the authorities state that a dry 
heat is the chief predisposing cause. In the present case the sender 
believes that the outbreak was in some way related to the raffia fibre used 
in tying. A sample sent had a white scurf here and there upon it, but,, 
under favourable conditions, this did not produce any fungoid growth. 
On examination with the microscope it was found to consist of fragments 
of plant tissues agreeing with the tissues of the fibre itself, and no doubt 
the dried remains of parts of the plant partially destroyed in the macera- 
tion and drying processes by which the raffia is prepared for market. 
The dry fibre is an unlikely source of infection, but, if any doubt existed, 
it could easily be sterilised by boiling, or by steeping for a time in a. 
2 per cent, solution of corrosive sublimate or otherwise. The universal 
remedy for mildews of the Oidium kind is sulphur. A discussion on a> 
hot-water method of treatment of the Vine mildew has been going on in 
recent numbers of the Gardeners' Chronicle.'" 
Diseased Cypripediums. — " Some flowers were recently sent which 
were checked in opening, apparently due to a collapse of the lower part 
of the flower-stalk. There were distinct signs of the presence of fungi, 
but it w^as not easy to say whether a mycelium was present or not. A 
request w^as made to the sender for portions of aft'ected plants. These 
arrived in excellent condition, and at first sight looked as hardy as one 
might wish. The older leaves w^re very fine, and showed no weak points* 
The older roots looked rather more dried up than one might wish, but 
