Ill 
After the meeting slides containing active molecules were 
exhibited to the members. 
A conversation took place on the preservation of dried plants, 
in which Mr. Bailey stated that he uses with success glue with 
carbolic acid for attaching them to the paper, as a preservation 
against mites, placing also a few crystals of the dry acid in his 
cabinet. 
At the meeting held on November 3rd, Professor W. C. Wil- 
liamson, F.R.S., called the attention of the Society to the struc- 
ture of the Calamite from the Upper Coal-measures represented 
in Pig. 478 of the 5th edition of Lyell’s ‘ Manual of Geology.’ 
He pointed out the existence of one Calamite within another, the 
former representing the pith and the latter the exterior of the 
bark, the pith and bark being separated by a well-defined woody 
zone. This woody zone consists of a series of tissues radiating, 
as in the recent Conifera, from the pith to the bark ; but instead 
of being all alike, they consist of two structures, which are 
arranged in alternating wedges. One of these is entirely com- 
posed of elongated cells, which being arranged in linear 
rows radiating from pith to bark, and being separated from the 
former by a defined line, this tissue is to be regarded as a modified 
form of pleurenchyma rather than of parenchyma. The interme- 
diate radiating lamina; or wedges resemble slices cut out of a 
coniferous Dadoxylon, having the same reticulated fibres and 
muriform medullary rays, the latter consisting of a single verti- 
cal row of cells. These structures replace corresponding wedges 
in the Calamites recently described by E. W. Binney, Esq., but 
in which latter the wedges consist wholly of masses of scalariform 
tissue unfurnished with medullary rays. Immediately below 
each node Professor Williamson pointed out the existence of a 
verticil of prolongations of the pith, penetrating the cellular 
wedges of the woody layer like spokes of a wheel. These he 
terms “ verticil! ate medullary radii,” to distinguish them from 
the ordinary medullary rays of the fibrous wedges. These fibrous 
and cellular wedges run uninterruptedly in a longitudinal direc- 
tion along each joint or internode of the Calamite, but at each 
node their arrangement is altered. If prolonged, the cellular 
wedges of one joint would run into the fibrous wedges of those 
above and below' it. But as the fibres of the fibrous wedges are 
continued from one internode to the other, they break up as they 
approach each node, their fibrous laminae being twisted in an ex- 
traordinary manner as they cross the node, in order to redistri- 
bute themselves right and left to the fibrous wedges of the joint 
above. In this part of the plant the fibrous laminae, aud medul- 
lary rays, and the cells of the cellular layer become intermingled 
in a remarkable way. At the base of each cellular lamina espe- 
cially the fibres radiate from a common centre in an almost 
inexplicable manner. 
