430 
The Coal of Australia. 
PLANTS. 
Class Ackogens. (Al. Lycopodales.) 
Ord. Maksileaceju (?). 
Vertebraria (Royle). 
This genus lias been proposed by Prof. Royle in his “ Illustra¬ 
tions of the Botany of the Himalaya Mountains” for two species 
of fossil plants from the supposed oolitic coal-field of Burdwan, 
but without any description or definition. Similar bodies are not 
uncommon in the shales and clays of the Australian coal-fields; 
but although the genus is noticed by Unger in his “Conspectus 
Florae Primordialis,” and Mr. Morris has noticed its occurrence 
in this district, no botanist has as yet given any descriptive ac¬ 
count either of the genus or species; and so obscure are the 
relations to other forms, that doubts have even arisen as to what 
part of the plant the radiated cylindrical fossils might be supposed 
to represent, and how its parts should be named. A distinguished 
botanist has suggested to me that the cylindrical fossil might be 
considered a stem, the axis being the pith, the radiating divisional 
lines the medulary rays, and the intervening cuneiform masses the 
wedges of wood. I have carefully considered this opinion, but 
find it impossible to adopt it, from the ease with which the 
transverse fractures take place, and the perfection of the surfaces 
produced, as it is obvious that such numerous and perfect divi¬ 
sional planes, as we observe at right angles to the axis, would be 
incompatible with the above view. On the whole, after a careful 
study of the specimens at my disposal, I feel disposed to view the 
genus as closely allied to Sphenophyllum, in which we have a 
jointed stem surrounded by verticillate whorls of from six to twelve 
wedge-shaped leaves with dichotomous veins; and in this light 
Vertebraria becomes intelligible, for I have clearly ascertained the 
existence of the dichotomous neuration on each of the wedge- 
shaped divisions of the transverse planes, which will, according to 
this view, represent the surface of a whorl of verticillate leaves, 
and we may consider therefore the main difference between 
Sphenophyllum and Vertebraria to consist in the greater ap¬ 
proximation of the whorls of leaves in the latter, the internodes 
