NationalLibraryOfScotland/medical-history-of-british-india huggingface dataset:
Medical Officers of the Army of India.
27
irregularly round and usually faceted, 18 x 16 µ, smooth, pale
orange-yellow. On Strobilanthes dalhousianus, Clarke.
II.—Uredopustules, circular, oval or linear, pale brown, hypophyllous, on
blades of leaves only. Spores round or pyriform, brown ; epispore
beset with prominent tubercles ; numerous capitate paraphyses
throughout spore bed. Spores 21.6 x 20.2 µ. On Pollinia
nuda, Trin.
III.—Teleutospore beds circular, oval or linear, dark brown or black,
hypophyllous, on blades of leaves only. Spores produced by
same mycelium producing uredospores, brown, free end rounded
and slightly thickened ; epispore studded with very minute tuber-
cles. Whole length of spore 36 µ and breadth at septum 16 µ ;
stalk 72 µ in length. Promycelia form four sporidia, measuring
1 0 x 6 µ
t o 1 2 x 7 µ
. O n P o l l i n i a n u d a ,
T r i n .
SIMLA ;
The 1st August 1886.
Schum., var. Himalayense.
BY
SURGEON-MAJOR A. BARCLAY, M.B.,
SPECIAL ASSISTANT TO THE SANITARY COMMISSIONER WITH THE GOVERNMENT OF INDIA.
(With Plates II, IV, and V.)
I was not aware, when during 1885 I traced the life history of the very strik-
ing æcidium which occurs abundantly on the nettles about Simla (Western
Himalayas), that a similar, if not identical, one is well known in Europe, and had
been described by Schröter.* Upon learning this I decided not to publish
the results of my own observations ; but, on reconsideration, I have thought that
it would not be uninteresting to those interested in these fungi were I to do so,
as the Himalayan variety differs in some respects from its European congener, and
is of peculiar interest in regard to its geographical isolation or at any rate remote-
ness. The traveller on the Himalayas is frequently struck by the presence
there of flowering plants very closely allied to, or even identical with, European
species ; but the occurrence of a similar heterœcious Uredine requiring two
widely different hosts for its existence is still more astonishing.
This Himalayan variety completes its existence on Urtica parviflora, ROXB .,
and Carex setigera , DON , while these two hosts are usually replaced in Europe
by Urtica dioica , L., and Carex hirta , Urtica dioica does not occur in the
Himalayas so far eastwards as Simla, although it is common enough farther
westwards in the Punjab and Afghanistan. The nearest allied species in Simla
to Urtica parviflorai s
G i r a r d i n i a h e t e r o p h y l l a ,
D E C A I S N E
, a l a r g e s t i n g i n g n e t t l e
with cut leaves which generally grows side by side with Urtica parviflora; but the
æcidium never occurs on it.
When Urtica parviflorais attacked by the fungus, very remarkable distor-
tions and hypertrophies are caused, an extreme instance of which is represented
in Fig. I, Plate IV. The fungus attacks both leaves and stem, but is always
localised; never pervading the plant generally and causing its complete destruc-
tion. When it occurs on the leaf, it is seen to have a special proneness to
attack the petioles or veins, and the parts invaded by the mycelium swell so
* Cohn's Beiträge zur Biologie der Pflanzen, Band I, drittes Heft, 1875.
† In the European variety, several other species of Carex, however, may bear the uredo and teleuto
spores, whilst Urtica pilulfera and U. urens may also bear the æcidia. See G. Winter, " Die Pilze
Deutschlands " (Rabenhorsts Kryptogamen Flora), and Schröter, l.c.
Medical Officers of the Army of India.
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places in the Sutlej Valley at elevations of 3,500 to 4.,000 ft., I found this fungus
already in full æcidial fructification.
Having given a brief description of the general characters of the æcidial
stage of this fungus, I will now describe some of the experiments made to show
that it is produced by teleutospores from Carex setigera.
Experiment I.
On the 21st June 1885, some teleutospores scraped off from their beds on
Carex were placed on the leaves of a nettle gathered some weeks previously
from a locality in which the fungus was not observed, and which, had since
remained unaffected in a small glass house in my garden. About a fortnight
later there were distinct evidences that the plants had become infected, as
several minute yellow spots were observed on the marked leaves which had
been inoculated. These spots gradually increased in size, and on the 10th July
'bore numerous ripe spermogonia. In the same glass house were several other
nettle plants which had not been inoculated, and these as well as the unmarked
leaves of the plant partially inoculated remained unattacked. The affected
parts continued to increase in area and thickness, and ultimately yielded charac-
teristic hypertrophies densely studded with ripe æcidia.
Experiment II.
A pot containing three seedlings raised from seed I had collected the
previous year and sown on 29th March 1886, offered 16 leaves in all for inocula-
tion. Upon 12 of these, scraped-off teleutospores were placed on the 6th June,
and the pot was then placed in a glass house outside. On the 26th June only
two leaves were affected, and no more became subsequently attacked. On the
4th July, a vein of one of these leaves was largely swollen, and under the
epidermies some æcidia were observed which a few days later came to maturity.
Experiment III.
A pot containing three similar seedlings had the terminal pairs of leaves of
each inoculated on the 6th June. The plants were then kept in my room under
a glass shade.. On the 14th three leaves showed commencing invasion, and on
the 26th five of the six inoculated leaves were attacked, and some bore ripe
spermogonia. The plants were not vigorous and had not grown since inocula-
tion. They did not form æcidia.
Experiment IV.
Seven similar seedlings had their terminal pairs of leaves inoculated on the
6th June, and were then placed, like those just described, in my room under a
separate glass shade. None of them became affected.
Experiment V.
Another pot also containing seven seedlings was treated in an exactly
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Scientific Memoirs by
similar way on the same day, but instead of being, then kept in my room was
removed to a glass house outside. On the 26th four leaves were found
attacked, and on the 4th July five of the seedlings had each its pair of inocu-
lated leaves attacked, whilst the remaining two seedlings showed each only one
leaf attacked. These plants had grown more vigorously in the glass house than
those similarly treated in my room (Experiments III and IV), for each plant had
unfolded two additional pairs of leaves above those inoculated, and these new
leaves remained quite free of the fungus. I think the small success attending
Experiment III and the entire want of success in Experiment IV may therefore
be ascribed to the unfavourable surrounding circumstances in their cases.
Experiment VI.
On the 7th June four leaves of a seedling were cut off, and their cut ends
placed under water. These were inoculated with teleutospores which had been
scraped off their beds, and which had thereafter lain 20 hours in water, by which
time numerous sporidia had been formed. Three of these became infected and
produced ripe spermogonia, but did not go on to the formation of æcidia.
Experiment VII.
On the 13th April some scraped-off teleutospores were placed on the leaves
of a young, uprooted, vigorous nettle gathered in my garden, and then placed with
its roots under water in my room under a glass shade, On the 24th I observed
that infection had undoubtedly occurred with paling of the leaf tissues and
bulging in all the inoculated leaves, and in one the formation of spermogonia
had commenced. Later several leaves formed spermogonia, but they all withered
before any æcidia were produced.
Experiment VIII.
I sowed some nettle seed gathered during the previous autumn in two pots
on the 29th March. On the 17th May these pots were crowded with seedlings
which had unfolded from one to two pairs of foliage leaves. They were then
sprinkled with a little water into which a large number of teleutospores were in-
troduced. On the 3rd June a great many leaves were attacked, and many
had produced ripe spermogonia. Later some æcidia were produced on a few
leaves, but most of the affected leaves withered early. In every case in which
æcidia were produced, the veins running across the affected areas were largely
swollen,
Experiment IX.
Six of these seedlings were uprooted prior to the commencement of Ex-
periment VIII, and having been placed with their roots under water, were inocu-
lated with the same material as was used in Experiment VIII, and then kept
Medical Officers of the Army of India.
33
under a glass shade in my room. Only one of these plants became infected, and
all withered early.
In reviewing the results of these experiments, some explanation seems
called for to account for the numerous cases in which infection did not follow
inoculation in experiments made upon seedlings. In the first experiment made
upon a fully grown plant, not only did all the inoculated leaves become attacked,
but all produced numerous æcidia ; whilst in the case of inoculated seedlings,
even when infection resulted, the growth of the parasite often advanced only
to the production of spermogonia. Two reasons may be given for the compara-
tive insufficiency of result in these cases. The first is that the seedlings were
very delicate from having been grown under artificial conditions : they were
mostly elongated and etiolated, and in some cases, as in Experiment VIII, too
densely crowded together. They were thus not robust plants, and could do
little more than nourish themselves. In the second place, we have seen that
this fungus requires considerable aid from its host for its own complete de-
velopment, as the ripe æcidia are always borne after the attacked parts have
swollen very considerably and amassed a large reserve of nutritive material.
In nature æcidia are never found except on very considerably hypertrophied
parts ; hence the seedlings were unable to nourish a parasite that demanded
so much of them in their enfeebled condition. These reasons, I think, will be
considered sufficient to account for the several failures in my experiments with
seedlings, more especially as they are indirectly supported by the complete
success attending my inoculations upon vigorous and fully developed plants,
many of which I have not thought it necessary to record here.
I will now proceed to describe the fungus as it occurs on Carex setigera.
This is a very widely distributed plant in Simla. Uredo pustules may usually be
found, though not abundantly, on its leaves, and sometimes on its stalks, during
the time the æcidia on the nettle are ripe,—that is, generally during July. They
occur mostly on the upper surface, and generally on the distal half of the leaf.
They are very inconspicuous, small, brown, linear or oblong sori.
At this time, while uredo pustules were common on the green blades, teleu-
tosporic pustules might usually still be found on the dried but still adherent leaves
of the preceding year's growth at the bases of tufts of these young leaves. These
pustules are also extremely inconspicuous on account of their minute size.
They are black and circular, often very numerous mainly on the upper surface, but
occasionally also on the lower. Towards the end of July and during August, new
teleutospore beds are formed on the green blades.
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Scientific Memoirs by
I made a few attempts to produce uredo pustules on Carex leaves in my
room by inoculating them with æcidiospores, but without success. The leaves
withered quickly in the room. I succeeded, however, in producing very numerous
pustules on tufts outside my house by dusting them with æcidiospores ; but it is
of course quite possible that the resulting infection may have been due to natural
attack, for the plants were not protected in any way. Still, as the plants which
Were in a naturally sheltered nook had been dusted very profusely with æcidio-
spores and bore many mote uredo and teleutospore pustules than are usually to
be found on naturally attacked specimens, the greater probability is that the
leaves in question became attacked by the æcidiospores I had dusted over
them. I did not consider it necessary to make further efforts to artificially re-
produce the Carex effection, as this had been done in Europe by Magnus as
related by Schröter in his work already quoted.
MICROSCOPIC CHARACTERS.
General. —The enormous hypertrophy of the parts attacked by this fungus is
due mainly to the increased size of the parenchyma cells, and, to a very subordi-
nate extent, to mycelial invasion. The mycelium never occurs in masses except
in the immediate neighbourhood of æcidia and spermogonia. Indeed, hyphæ in
any large numbers are only to be seen to a depth of about three or four cells
beneath the bases of æci di a. El sewhere si ngl e fi l aments are seen coursi ng
throughout the hypertrophied tissues. They are also to be found between the
elements of the fibrovascular bundles, though sparingly. There is therefore no
general separation Of the parenchymatous cells. The hyphæ are very translu-
cent (and therefore difficult to detect without staining), septate, branched, and
Measure on an average from 4 to 5 µ in diameter.
The mycelium penetrates some of the cells forming haustoria of the
branched type. Sometimes the haustorium consists of a single slightly con-
voluted twig, at others it is arborescent (Figs. 4 and 5, Plate IV). They occur most
abundantly within the parenchyma cells adjoining those immediately surrounding
the fibrovascular bundles (bundle sheath cells), and are best seen in longitudinal
sections: They occur also in other cells of the parenchyma as well as in the
sheath cells themselves. The contents of these haustoria are very finely granu-
lar, and in this respect differ from the hyphæ generally, which, as already observed,
are very translucent. They may also be seen in the leaf tissues, both in the
spongy, and palisade cells (Fig. 21, Plate II).
The hypertrophied cortical parenchyma cells are filled densely with large
granules; which are apparently of the nature of starch, for they become deep blue
on the addition of Schultze's solution (chlor. zinc. iod.), but they do not exhibit any
traces of striation nor of hila. With Spiller's purple, these grains are sharply dis
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Scientific Memoirs by Medical Officers of the Army of India.
parellel rows, but in the Indian variety they are isolated, small, circular beds.
The teleutospores in both forms are of about equal total length; but whilst
in the European form the lower cell is often-longer than the upper, the reverse
is the case with the Himalayan variety. The stalks of the European form are
about 20 µ long; in the Indian variety they are about 56 µ long. The sporidia
in the European form measure 10 x 6.6 µ, whilst in the Indian variety they are
12 x 8 µ;and whilst the former appear usually to form secondary sporidia, the
latter do so very exceptionally.
PUCCINIA URTICÆ, nov. sp.
P.S.—The leaves of Urtica parviflorao f t e n , b e a r n u m e r o u s t e l e u t o s p o r i c
pustules during the autumn long after all trace of the æcidial affection above
described has disappeared and when the plants are in flower. I have counted as
many as 120 pustules on a single leaf-blade. This affection has apparently no
relationship whatever with Æcid. urticæ, for when the spores are placed upon
sound nettle leaves no result follows. It must therefore be related to some other
æcidium; but in spite of numerous attempts by experimental inoculations to
discover its future history, I have failed entirely to do so. The pustules vary in
size from that of a pin' s head 3 m.m. in diameter. These pustules are on the
under surfaces of the leaves; they are deeply convex there with a corresponding
concavity above. The invaded areas are at first pale yellow both above and below,
but later they become brown below, whilst above they are orange-yellow with a
pale-green margin. The pustules consi st of aggregations of minute, circular,
prominent spore-beds. The spores are borne on long stalks, and are very firmly
adherent to the leaves. They are brown with a thick epispore, thicker at the apex
than elsewhere, and show no surface markings (Fig: 18a, Plate V). The spores vary
greatly in size and shape, an average one measuring about 40 µ in extreme length,
of which 18 µ belong to the upper cell and 22 µ to the lower, whilst the extreme
breadth of each cell was 17 µ. An attenuated spore measured 38 µ in length by
only 8.5 µ in width, whilst a plump spore measured 40 µ in length, the upper cell
being 19 µ wide and the lower 14.8 µ. An abnormal double-headed spore is, shown
in Fig. 18 b, Plate V, and such spores are not rare. Some freshly-collected
spores placed in water on 11th September germinated freely in 24 hours, each
cell throwing. out a promycelium, that from the upper cell emerging from the
apex, and that from the, lower cell from a point near the septum. The promycelia
are usually long, straight, colourless tubes, measuring generally 8 µ in diameter at
their bases, but sometimes only 6 µ, and diminishing gradually to 2, or 3 µ at their
apices. My cultivations in pure water never attained to the perfect development
of sporidia, but apparently the terminal ends of the promycelia divide into three
compartments, from each of which one sporidium is formed measuring 12 x 8
µ
SIMLA;
The 3rd August 1886.
On the Phenomenon of Gaseous Evolution from the Flowers of
Ottelia alismoides.
BY
SURGEON-MAJOR. D. D. CUNNINGHAM, M.B.,
SPECIAL. ASSISTANT TO THE SANITARY COMMISSIONER WITH THE GOVERNMENT OF INDIA.
(With Plates VI, VII, and VIII.)
Ottelia alismoides is a plant very abundant in the tanks in and around
Calcutta, and, along with Vallisneria spiralis, stands out conspicuously as an
important source of oxygen supply to the water. Certain peculiar phenomena
connected with the gaseous evolution from the plant have not, in so far as I know,
been specially described, and in the present paper I propose to give a brief
account of them, founded on observations which were in greater part carried
out in the early part of the year 1885. During the greater part of the time
in which any plant of Ottelia is in full vigour the evolution of gas from it is not
of a character to attract casual attention, as it is carried out by means of an
abundant ascent of minute bubbles from the edges, and, to a slight degree,
from the upper surfaces of the large, broad leaves. The great site of discharge
of gas from the tissues is at this time the inferior surfaces of the leaves. The
large amount of gaseous evolution actually occurring under such circumstances
becomes, however, at once evident on removing a plant from its natural site
and introducing it into a glass jar full of water and exposed to sunlight. A
continual stream of small bubbles is then seen ascending from the foliar sur-
faces.
Such phenomena continue to present themselves unaltered during the period
of growth of the scapes and early development of the flower-buds, but during the
single day in which any flower matures and blows they are to a great extent
replaced and masked by others. The gaseous evolution at this time becomes ex-
tremely conspicuous owing to the constant discharge from the flower of a stream
of bubbles of such considerable size as to be readily observable whilst the plant
remains in its normal site, and the flowers deeply submerged, as the majority
of them are, beneath the surface of the water.
The general sequence of events in the blooming of the subaqueous flowers of
Ottelia (Plate VI, Fig. I) is as follows: The actual flower-buds, up to the day on
which they expand, are completely enclosed by a continuous sheath of fused bracts,
forming a tube around the elongated ovary and arching over the young calyx and
ar
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Scientific Memoirs by
ordinary circumstances these are mainly represented in the delicate tissue of
the inferior foliar epidermis, and the excess of gas is accordingly forced out
between the delicate cells there. Under other circumstances, however, the point
of least resistance may come to be situated elsewhere; for example, if the petiole
of a leaf freely exposed to sunshine be carefully divided by a sharp knife, a very
considerable continuous discharge of gas manifests itself from the end of the
laminar portion of the petiole, while a certain amount also frequently appears
from the end of the axial portion. On the other hand, if the scape of a. flower
which has already blown be similarly treated, a large continuous discharge of
gas occurs from the axial extremity, while none appears from the floral one.
The floral apparatus during the earlier stages of maturation appears merely
to represent the temporary point of least resistance in a system exposed through-
out to high gaseous tension. That it should do so is readily accounted for by
the special delicacy and open characters of the tissues composing it and directly
continuous with those of the scape in which, as the experiment just cited shows,
conditions of high gaseous pressure are present. But these conditions can be
experimentally shown (vide Note B) not to be dependent on processes of local
manufacture there, but on processes of gaseous manufacture in the leaves, the
pressure originating there being propagated along the continuous system of
petiolar stem and scape intercellular spaces.
In Ottelia, then, we have a great continuous system of intercellular spaces,
which under the influence of sunlight becomes highly charged with gaseous
contents. As there are no permanent special openings, such as stomata, pro-
vided for discharge, the gaseous tension within this system goes on increasing
until discharge is effected at the weakest points in it. Under ordinary circum-
stances these are mainly situated in the leaves, and specially in the under surfaces
of these. When, however, the flowers are maturing,—when the buds become
exposed by the rupture of the protective bracteal cap which had previously
covered them,—the delicate floral tissues become the weakest points in the sys-
tem, and gaseous discharge, accordingly, mainly takes place by means of them.
After fertilisation has occurred and the flowers have finally expanded, two things
combine to cause a cessation of this floral evolution; for in the first place the
corolla, stamens, styles, and stigmas rapidly pass on into decay and fuse into a
common, brownish, gelatinous mass on the summit of the ovary; and in the second
the process of fertilisation is followed by an excessive secretion of tough mucoid
material within the ovary which blocks up the cavities of the loculi and presses
upon the delicate open tissues surrounding them. The flower-stalk thus ceases
to be the readiest channel for discharge, and the ordinary foliar discharge recurs
until the period at which another flower matures.
CALCUTTA;
The 10th April 1886.