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gens, and, after alluding to the peculiarities of structure that had 
drawn towards these plants the attention of all physiologists, he pro- 
ceeded more particularly to detail his observations on the anatomy of 
their wood-cells. The structure and development of the wood-cell 
had been well-elucidated by Hugo von Mohl, in various papers in the 
- © Annales des Sciences Naturelles,’ and in his work on ‘ The Vegetable 
Cell,’ but there was one aspect in which the subject had not been so 
fully viewed as appeared desirable. Mr. Lawson’s examinations had 
been undertaken principally for the purpose of ascertaining in how 
far the peculiarities in the minute anatomy of the Conifer coincided 
with their general structure, and might be depended upon in the de- 
termination of their orders, genera, and species—an inquiry, from 
which fossil Botany and investigations relative to timber were likely 
to derive advantage. After detailing the general structure of the wood- 
cells of Coniferze, and pointing out peculiarities that occurred in va- 
rious plants of the order, he described a remarkable modification 
which had been noticed in the yew, viz. the presence in the wood- 
cell of what appeared to be a spiral fibre, but which had been shown 
by Harting to be a connected pellicle with thickened ridges arranged 
in a spiral manner. Mr. Lawson had found this structure to be by no 
means so rare as had been supposed, and although principally con- 
fined to plants belonging to Taxacez, it was stated not to be univer- 
sal in that order, nor peculiar to it. He had observed it in the 
following plants :—Cephalotaxus Fortunii C. pedunculata, C. tardiva, 
Torreya taxifolia, T. nucifera, Taxus baccata, T. canadensis, Podocar- 
pus japonica, P. Koraiana, Abies Douglasii, and Fitzroya patagonica. 
It also occurred in a specimen of pine-wood from N. California, which 
presented interesting microscopical characters, but which he had been 
unable as yet to identify. This structure was not to be confounded 
with the faint spiral streaks seen under a high power on the secondary 
membraue of: the wood-cells of many Conifere. It had been long a 
question whether true punctated tissue was strictly confined to Gym- 
nogens. A careful examination of Drimys granatensis and other 
plants had led Mr. Lawson to believe that the disks which occurred 
in aromatic trees were essentially the same as those of Conifere, and 
indeed accorded in a remarkable manner with those of many Arau- 
cariz and Taxacez, in which the central dot was not circular, but 
formed by two elliptical slits crossing each other. The manner in 
which this appearance arose was fully explained by a reference to the 
spiral arrangement of the slits, which also seemed to account for the 
alternation of the disks in Araucaria. In the determination of fossil 
