68 
country and is sometimes met with in remarkably fine specimens, 
which have an Elm-like appearance. It is more ornamental than 
the type, and moreover differs from it in having more or less 
pubescent young branches and petioles. This interesting tree was 
first described by the younger Michaux as Populus hudsonica and 
shortly after by Pursh as P. betulifolia, from specimens found 
growing on the Hudson River and about Lake Ontario, where it 
had apparently been introduced, almost certainly from Europe. 
The Campanula is a native of Transcaucasia and Northern Persia, 
and the plant figured was raised at Kew from seed received from 
the Botanic Garden, Tiflis, Caucasus. It has pale blue, broad, 
campanulate flowers about 1} in. across. Rhododendron Keiskei is 
a Japanese species with rather small greenish-yellow flowers in 
clusters of 3 to 5. The illustration was prepared from a plant 
which was procured from a Yokohama nursery in 1208. Agonis 
marginata is a pretty myrtaceous shrub, from Western Australia 
which has been figured from a specimen grown in the open in the 
garden of Mr. T. A. Dorrien Smith, Tresco Abbey, Isles of Scilly. 
_ Witches’ Brooms of Gacao.— Under the above title, an abstract was 
given in the Bulletin, 1909, p. 223, of an investigation conducted 
by Dr. C. J.J. van Hall, Inspector of Agriculture in Dutch Guiana, 
and Mr, A. W. Drost, who not only indicated the cause of the 
formation of Witches’ brooms on the cacao plant, but also the 
origin of the diseases attacking the pods of the same plant. An 
English translation of this important paper, accompanied by the 
illustrations present in the original, has just appeared in the 
“ Proceedings of the Agricultural Society of Trinidad and Tobago,” 
vol. ix., December, 1909, pp. 475-562. The following points in 
connection with preventive measures were not included in the 
previous abstract in the Bulletin. 
o far as has been ascertained, the fungus causing Witches’ 
brooms and the pod disease, is confined to the cacao plant. Most 
brooms, hardened pods and infected cushions which a diseased tree 
bears, a removal of the entire leaf-bearing crowns of the tree 
becomes imperative, so that after all the leaf-bearing branches are 
cut off, nothing remains but the trunk and leafless main branches. 
After this operation the tree should be thoroughly sprayed with a 
three per cent solution of sulphate of copper. Trees thus treated 
form new crowns in a surprisingly short time. Cutting back 
should be done at the commencement of the principal dry season of 
the locality. 
To ensure success cutting back should be conducted simultane- 
ously over as large an area as possible. All pruned branches 
should be promptly burned. 
Sa © 
