Linnean Socrety. 353 
December 2.—E. Forster, Esq., V.P., in the Chair. 
Read a paper ‘“‘ On the Anatomy of EHriocaulonee.” By the late 
William Griffith, Esq., F.L.S. &. Communicated by R. H. Solly, 
Esq., F.R.S., L.S. &c. 
The observations on which this memoir (written at Calcutta in 
1835) was founded, were made at Mergui between the months of 
July and October 1834. The species examined were natives of that 
place, and six in number. They appear to be destitute of true spi- 
ral vessels, the place of which is supplied by ducts occasionally, but 
not freely, unrollable, aggregated in distinct fascicles and surrounded 
by more or less elongated cells. 
Mr. Griffith describes the leaves of Eriocaulon setaceum, L., as the 
type of these organs in the genus, since they are in it reduced to 
the simplest state. They are submerged in this species, and the pe- 
duncles and their. sheaths only rise above the surface of the water. 
The leaves are subulate, somewhat flattened and colourless below, 
green on their upper surface, and divided throughout their entire 
length into two distinct collateral tubes, by means of the central and 
only nerve which is attached both to the superior and inferior cutis 
by cellular tissue. Numerous transverse septa of cellular tissue 
divide each tube into chambers, which, however, have free commu- 
nication with each other through fissures dependent on a partial 
separation of the cells. The green parenchyma is almost entirely 
confined to the upper half of each tube, and ceases abruptly with- 
out any apparent cause. It consists of a single layer of colourless 
oval or roundish sacs, arranged with the most beautiful regularity in 
longitudinal lines extending from the base to the apex of the leaf, 
and corresponding with the bodies of the cells forming the cutis and 
not with the intervals between them. ‘The stomata are confined to 
the under halves of the leaves, or to-that portion of the tubes which 
is destitute of parenchymatous tissue. 
In the terrestrial species the structure of the leaves is essentially 
the same, but the number of longitudinal tubes is increased, and va- 
ries from six to twenty, the central ones only reaching the apex of 
the leaf. The longitudinal divisions between these tubes are marked 
externally by corresponding depressions, and each is furnished with 
a vascular fascicle similar in structure and position to that of Z. se- 
taceum. ‘The parenchymatous cells are arranged with less symme- 
try than in that species, and are not so completely confined to the 
upper surface ; and the lower surface abounds with stomata. 
The sheaths which envelope the base of the peduncle have in all 
the same organization, which is exactly that of the leaves of the ter- 
restrial species. ‘The peduncles are also composed of tubes, circu- 
larly arranged; they are marked externally with elevated whitish 
lines, which (in the living plant) have a slightly spiral direction 
from left to right, and correspond to the longitudinal septa. The 
tubes meet in a cellular axis, around which the vascular fascicles are 
arranged in corresponding number; and the septa form so many 
spokes consisting of more or less elongated cellular tissue, which in 
