68 NATURAL HISTORY. [NORTH 
species of Calamites , almost all from the rocks of the most ancient coal 
formation, are far from being satisfactorily determined, their internal 
structure being entirely unknown. The species of Calamitea of Cotta, 
(Case E.,) which exhibit a peculiar organic structure, can scarcely be 
said to belong to the same natural order. The genus Phyllotheca of 
Brongniart, from the coal sand-stone of Port Jackson, in which the 
sheaths are prolongated into leaves, is a distinct genus of this order; as 
is likewise the Equisetum Lyellii from Pounceford. 
The lower division of Case 2, and part of 3, contain the Ferns (Fi- 
lices), most of them as impressions in clay slate forming the carboni¬ 
ferous strata of the transition series. Many of them bear a strong re¬ 
semblance to existing, especially tropical, species ; and fructification, 
distinctly exhibiting the sporangia variously disposed in sori, &c., has 
latterly been observed in several species; but the classification founded 
on characters derived from them and the distribution and ramifications 
of the nerves, though of great importance in the classification of recent 
ferns, is obviously, at least in the present state of our knowledge, inap¬ 
plicable to those in a fossil state. The arrangement and the generic 
names here adopted, with occasional deviation, are those proposed in 
the concluding numbers of the late Count Sternberg’s work. The 
species, as far as determined, are all named; the synonymy being added 
in most cases where it appeared requisite. 
In the upper division of Case 3, and part of 4 and 5, are placed 
those genera which are generally supposed to belong to the family of 
Lycopodiace^e, of which Lepidodendron of Sternberg ( Sagenaria of 
Presl.) is the principal one. Much uncertainty still prevails in the deter¬ 
mination of the genera and species of this family. Some of them ap¬ 
pear to exhibit an internal structure intermediate between that of the 
Lycopodiacese and the Coniferse; but Lepidodendron punctatum of 
Sternberg, (of the unique specimen of which, in Mr. Cotta’s collection, 
a portion is seen in Case 3,) presents the organization of a real arbo¬ 
rescent fern. Nearly allied to the Lepidodendra are several vegetable 
fossils, considered as distinct genera, among which may be specified 
Lepidophyllum and Lepidostrobus (Case 4) of Brongniart, (the 
former perhaps only the leaves, the latter the fruits of spbcies of Lepi¬ 
dodendron or Lycopodites,) the Ulodendron ( Lepidod . ornatissimum , 
Sternb.), the Bothrodendon of Lindley, the Rhytidolepis of Sterab., &c. 
In the upper division of Case 5 are placed the species of Sigillaria , 
(including Favularia ,) Brong., which are very distinct in their structure 
from arborescent Ferns, with which they have by some been arranged. 
To these also belongs the Megaphyton Nbhd. ; of which the original 
specimen figured and described by Artis is deposited here. In the 
lower division of the same Case, are seen some very interesting vege¬ 
table remains, some of which undoubtedly are referable to the family of As- 
PHODELEiE, such asth e Draceena Benstedii, (from the Iguanodon quarry 
near Maidstone,) so called after the discoverer of the fine specimens pre¬ 
sented to the Museum. To these are added very perfect specimens, 
from Dr. Mantell’s collection, of the Clathraria Lyellii from the Weal- 
den : the generic-name, formerly synonymous with Sigillaria, is now ex¬ 
clusively given to this remarkable vegetable. Sternbergia transversa 
of Artis, ( Artisia of Sternberg,) hitherto described and figured from 
very imperfect specimens, also probably belongs to this natural order. 
