xlviii Journal of Proceedings.
scientific journals he had recently consulted when working out the
bibliography of the Infusoria, and would endeavour to hunt up the
reference for Mr. Lister. He hoped Mr. Lister would not be discouraged
from the fact of the observation not being altogether original, and he had
no doubt that many data of importance and interest had yet to be
registered in connection with this singular phenomenon. The enigma
submitted to the members by Mr. Lister as to how the Rotifers got inside
the cells of the Vaucheria, no perforation or other means of ingress or
exit being apparent in the tissues of the plant, was somewhat akin to that
proposed by a certain sagacious British monarch—as to how the apples
got into the dumplings. The occurrence of Rotifers, Infusoria, Rhizopods,
and other lower organisms within the tissues of living plants was by no
means rare, and was doubtless brought about by the invasion by the
animal, in either its adult or larval condition, of the plant through some
overlooked weak point, such as a decaying cell or mutilation of the
adjacent tissues. The relationship of the wart-like excrescences to the
enclosed Rotifer in the case of Vaucheria was apparently analogous to
that of a gall to its contained insect, the excrescence being simply an
abnormal growth of the plant-tissue produced by the local stimulus. A
like interpretation, so far as he could remember, was suggested in the
paper bearing upon this subject previously referred to.
Mr. W. W. Reeves, Dr. Cooke, and the President also took part in the
discussion, after which Mr. Lister read a second note as follows:—
Note on the Occurrence of Carex pseudo-cyperus and the Flowering
of Lemna gibba in Wanstead Park, Essex.
" On the 4th of July last (1882) I visited the grounds of Wanstead
Park, which are soon to be thrown open to the public, when they may
perhaps lose something of the secluded wildness which they have enjoyed
for many years, and when the native fauna will at least be added to by
the introduction of semi-domesticated water-fowl.
" But as yet the only change that strikes one consists in the laying down
a gravel path along one margin of the lake; and it would be well worth
the while of members of the Club to obtain tickets and see the locality in
its hitherto undisturbed beauty.
" I came upon the lake by a narrow wood path and, cautiously emerging
into the open, had the pleasure of watching at no great distance a group
of some sixteen herons preening themselves in graceful attitudes upon
the pathway ; their dove-coloured plumage, lit up by the bright sunshine,
finely set off by the dark foliage behind. A Moor-hen was sitting on its
nest, raised as a little island above the water, while the thicket resounded
with the song of the blackcap.
" The lake is fringed with a rank growth of Glyceria aquatica, at the
time of my visit gemmed all over with countless numbers of slender blue
Dragon-flies. The lower growth is made up of Comfrey, Greater Skull-
cap, Loose-Strife, and many other marsh plants. Among the Carices,
now in full ripeness are Carex riparia and C. vulpina, and the rarer
species Carex pseudo-cyperus, a specimen of which I have brought with me.
" The ' London Catalogue ' gives forty-five local districts in which it has
been found in the kingdom, including the Channel Islands, but it was the
first time I happened to have met with it.