ec 
CLATHRARIA LYELLII. Léa 
I have spared neither trouble nor expense in endeavour- 
ing to detect the organization of this plant ; numerous 
sections of stems have been cut, and ex- ag 
amined microscopically, but very few exhi- . 
bit any traces of structure ; and in those 
which retain some vestiges of organiza- 
tion, the siliceous mass which permeates the 
vascular tissue, is not sufficiently transpa- 
rent to yield satisfactory results. It can 
only be inferred that in their internal or- 
ganization, as in their external characters, en 
the Clathrarize were most nearly allied CraTHRanra 
to the Cycadec or Zamiee. A remarkable 7 aan a 
specimen, (Lign. 56,) discovered in a stra- —Tiigate Forest. 
tum of Chalk-marl, near Bonchurch, con- Le dare the wer: 
firms this view, and throws much light trices of the petioles ; 
on the nature and relations of these vege- alles ee 
tables. cortical cylinder. 
This fossil is a portion of the summit of a stem gar- 
nished with persistent petioles, or leaf-stalks: it is fifteen 
inches in length, and nearly per- 
fect at the top; and at the 
lower end, which has been bro- 
ken off transversely, the inner 
axis (Lign. 56 a.), surrounded 
by the false bark formed by the 
confluence and consolidation of Lien. 55. 
the bases of the petioles, is ex- PETIOLE or ChaTHRaRIA LYELLII; 
posed. The stem has been stript e igcmanic yt 
of the leaf-stalks at the lower- - Vascular ae left by the separa- 
most part, and exhibits the cha- tion of the leaf. 
racteristic lattice-like scars. The 
petioles are for the most part entire ; some of them are abor- 
tive, and others, which have supported leaves, are marked 
on the summits with vascular pits, indicating that the foliage 
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