542 THE TROPICAL AGRICULTURIST. [Feb. 1, 1900. 
he disease to neighbouring trees. Further details 
must, of course, be worked out on the spot, but I 
Btrongly advise early action or the spread o£ the 
enemy may be too quick and we may lose some of 
our finest and most promising areas of reproduction. 
These few examples ouKht to show sufEciently 
clearly how very important the subject is, and if we 
are to utilize to the full the information obtained 
in, and the experience of, Europe, we must begin 
by searching for and finding the sporophores and 
obtaining their identification. The identity «£ the 
fungus which attacks the stems of the Kharshu 
( Qxiercussemicarpifolia) trees at Deoban in Jp.unsar, 
requires to be investigated. From the fact that it 
ia apparent both in the mycelial form of white threads 
disintegrating the wood, and in the form of long 
black stout rhizomorphs it is most probably the well- 
known Agaricus melleus or an allied species, but 
the discovery of the sporophores is necessary in order 
to settle the question. 
In the case of Hymenomycetous fungi like those 
already mentioned, it is not always easy to find the 
sporophore and identify the enemy ; but in other 
cases, and especially in the case of 
THE LEAF-DISEASES, 
it is not so difficult. Most of those who have worked 
in the sub-Himalayan sal forests have noticed that 
in some years the leaves of the trees, often over con- 
siderable areas, appear as if covered with soot. A 
very little examination of the effected leaves shows 
that the black appearance is due to a fungus, but al- 
though the spores of the fungus were readily found, 
its nature remained for some time in doubt. Speci- 
mens collected by myself in Dehra Dun and by Pandit 
Keshavanand in the forests of Ondh were sent to Dr. 
D D Cunningham, F.A.S., of Calcutta, and his report 
was that the blight was a Meliolaceous Pyrenomycete 
not parasitic but merely epiphytic and that 
where they do any injury to the host, it is purely due 
to their interfering with assimilation and respiration 
from the dense surface-coating which they ultimately 
tend to form." A note on the subject appeared in the 
" Indian Forester " Vol. XX, p. 156 and further speci- 
mens were sent to Kew where they were identified as 
Meliola ampJntriclia, Fries. Thus two investigations 
were satisfactory and showed that after all, unless the 
fungus was very bad indeed, it was not to be expected 
that it would cause greater injury to the sal forests 
than a slight retardation of growth. So is it also, 
generally, with the well-known conspicuous orange- 
coloured uredineous fungi which occur on the leaves of 
Jlimalayan conifers and which were the chief subject 
of the paper in the " Indian Forester," Vol. XXI, p. 
126, by Mr. J. Nisbet, with pictures from photographs 
taken by Mr. 0 G Rogers. The chief of these was the 
yellow tassel-like fungus on the young leaves of Picea 
Morinda called by Mr. Nisbet JEcidium Thompsoni and 
identified at Kew as Feridermium incarcerans, Cke. and 
by Barclay as P. picecc Barcl. This bright -looking fungus 
is, as Mr. Nisbet pointed out, closely allied to the P. 
coruscans, Fries, which attacks the spruce tree of Europe 
and is occasionally eaten by the peasants in the north, 
and I believe it is itself occasionally used as an article 
of food in the Himalaya. The damage done by it 
ia not very great unless it happens to attack the 
principal leading shoot of the tree. Then there were 
also the Peridermia of the pines, Pinus lonyifoKa, 
arid P. C'Xcclsa, identified at Kew as reridermium 
oriontale, Cke. These appear as small orange-coloured 
sacs of spores on the needles of the trees here and 
there, but do little harm unless they occur, as Mr. 
Nisbet points out, on the branches in the form of the 
var, roriicola. They have been described, in more detail, 
in Mr. Nisbet's paper already referred to, as well as in 
Dr. Cooke's paper in the "Indian Forester." Vol. 
Ill, p. 88, The Peridermium pini of Europe, which 
is found on the Scots pine, is known to be in its 
loaf-attacking variety the aoci dial form ol ColcnSporium 
scnecionis, a fungus which attacks the groundsel, buj 
the corresponding alternate plant of the 7'. oriental^ 
has not yet been discovered and here there ig 
Bomo acopc for the investigator. As regards thg 
alternate from of the var. eoHicola, Hartig says. — 
' It is to be regretted that so far the plants have not been 
' determined on whicli the teleutospores are produce'. 
Until we discover the teleuto form, preventive mea- 
sures must be confined to felling pines that are 
attacked." Dr. Barclay thought that the form son Piims 
lono'ifolia and Pinus exceUa were distinct, and named 
them, respectively, JLcidiam complanatum, Bare), and 
yE. Irevms, Barcl. (see Jour. As. Soc. Beng. lix. ii. 
101-102). He thought at one time, that the latter 
might possibly be the ceeidial form of Clirysomyxa 
himalayeiiKis, a bright orange-coloured fungus very 
common on the petioles of the leav- s of Rhodudcudron 
trees in the hill forests, but afterwards changed his 
mind and considered that the alternate host of the 
latter would more probably be Picea Morinda and 
the fungus ^Ecidiurn pice(e (see Scientific Memoir of 
Medical Officers of the Army of India, Pan VI 
1891, p. 71.) 
An interesting example of alternate generations 
in fungi is given by Dr. Barclay in the same Scien- 
tific Memoir, Part V 1890, p. 71, where he shows 
that the Gymnosporangium Cunninyhamianum which 
grows on Chjpressus torulosa, Don, has its secidial 
form on the wild pear Pyras Pashia, The cvpress 
fungus is that one which may be seen in abundance 
about Bodyar in Jaunsar, having, in wet weather, 
tlie form of gelatinous yellow masses. Nisbet in the 
'Indian Forestei,' XXI, 132, speaks of these as a 
Nosioc or alrja, bat this is not mentioned by Barclay. 
Another example, perhaps the best known example,' 
is that of the, ' 
' EUSTS ' OF WHEAT, 
and other cereal crops and grasses. A very full account of 
these rusts was published in 1897 by Dr. Prain of the Royal 
Botanic Gardens, Calcutta, in 'Agricultural Ledger' No. 
16. in which he explains how, among others, the 'Black 
rust' (Puecinia rjraminis) which attacks wheat, oats 
barley and rye, as well as other grasses, has its oecidial' 
stage on species of barberry (Serheris) ; the 'Brown 
rust ' (P. dispersa) which attacks wheat and rye and 
other grasses has its Mcidial stage in various species 
of the ' Borage ' family ; and the ' Crown rust ' 
(P. coronata) which attacks chiefly oats and other 
grasses has its aacidial stage on various Buckthorns 
(Rhamuus Berchemia, etc). Dr. Prain explains how 
it is not yet known exactly whether the common 
rusts of India have their ascidi?i stages on other 
plants, and if so, what plants these are, but we do 
know that fficidia of a fungus which has at Kew 
been identified as Puecinia ciramims has been found 
on Berheris aristata, that Puecinia coronata has been 
identified as attacking Bhamnus purpitreus and rirqatus 
and that a fungus described by BIr. Barclay as Uredo 
eJiretice has been found in the Himalaya attacking 
the Boraginous tree Ehretia serrata, and may be 
possibly identical with Puecinia dispersa; so that 
there is every reason to think that, at any rate in 
the neighbourhood of the north-west Himalaya the 
principal rusts of the cereal crops are traceable to 
the leaf-fungi of Himalayan forest trees and shrubs. 
The pages cf the ' Indian Forester ' contain several 
article.s of interest on the subject of Indian parasitic 
fungi, and more especially can we draw attention 
to Dr, M. C. Cooke's admirable papers in Vol. II. 
p. 380, and Vol. Ill- p- 14. Dr. Cooke was also 
good enough to name for me some specimens collected 
by myself and others, and these are mentioned in 
Vol. IV. page 90 and page 197, 
The chief workers in the field of the Indian fungoid 
diseases of plants have been Dr, D, D. Cunningham, 
F. R, S., who has lately retired from service in 
broken health after many years of hard work in 
Calcutta ; and Dr. A. Barclay who died in 1891 at 
Simla of typhoid fever at the early age of 39, to the 
great regret of his many friends and correspondents, 
and to the great loss of Indian scientific work. A 
notice about him and his work will be found in the 
" Indian Forester, ' Vol. XVII. page 303, 
