intermediate character of CYCADEjE. 493 
points within the buds), they resemble Ferns. 
(See PI. 1 . F. 33, 34, 35, and PI. 58, 59.) 
I shall select the family of Cycadese from the 
Fossil Flora of the Secondary period, and shall 
enter into some details respecting its organization, 
a view of showing an example of the method 
analysis, by which Geologists are enabled to 
Arrive at information as to the structure and 
Economy of extinct species of fossil vegetables, 
^od of the importance of the conclusions they 
^re enabled to establish. Those who have at- 
tended to the recent progress of vegetable Phy- 
siology will duly appreciate the value of micros- 
copic investigations, which enable us to identify 
the structure of vegetables of such remote anti- 
quity, with that which prevails in the organiza- 
tion of living species. 
The physiological discoveries that have lately 
^oen made with respect to living species of Cy- 
cadeae, have shown them to occupy an inter- 
mediate place between Palms, Ferns, and Co- 
*^iferae, to each of which they bear certain points 
resemblance ; and hence a peculiar interest 
attends the recognition of similar structures in 
tossil plants, referrible to a family whose charac- 
ters are so remarkable. 
The figure of a Cycas revoluta (PL 58,)*^ re- 
presents the form and habit of plants belonging 
te this beautiful genus. In the magnificent crown 
* Hrawn from a Plant in Lord Grenville’s Conservatory at 
■^roptnore in 1832. 
