436 Carruthers—On a Fossil Cone from the Coal-measures. 
ment of the larger organs. Such cones are figured by Lindley and 
Hutton in their ‘ Fossil Flora ;’ but as the sulphide or carbonate of 
iron into which they are converted is only a cast of the organism, 
and does not exhibit structure, it is impossible to determine with 
certainty their affinities with recent vegetables. The conclusion of 
the authors referred to seems to have been, on the whole, that they 
were Coniferous; although sometimes they lean to the opinion that 
they are Lycopodiaceous, or somewhere intermediate between the two 
families. The materials which Brongniart had to work with, though 
more extensive, were not in a better condition. In the second 
volume of his ‘ Histoire des Végétaux Fossiles’ (unfortunately im- 
perfect), he enters into an elaborate examination of their affinities, 
and shows that they are nearly related to Lycopodiacee, even though 
he was ignorant of the contents of the organs borne on the scales. 
In the text he describes the sporangia as attached to the under sur- 
face of the scales, showing an affinity, as he supposes, to Ferns ; but 
in the magnified illustration of two scales and the related sporangia, 
he places them rightly, as is evident from the imbrication of the 
apices. The misconception probably arose, as Dr. Hooker suggests, 
from his mistaking the base for the apex in the cone to which the 
two magnified scales belong. (Op. cit., pl. xxiii., figs. 2 & 26.) 
Robert Brown had the singular good fortune to obtain in 1843 
the upper half of a silicified cone, which, when prepared, for the 
first time exhibited not only the arrangement of the different parts, 
but their microscopic structure,—and, what was of much more im- 
portance, showed that the seed-like bodies, supported by the scales, 
were sporangia filled with spores composed of three, rarely of four, 
sporules. The value of this fossil was shown by Mr. Brown in his 
communication read to the Linnean Society in 1847, and published 
with drawings in the 20th volume of their ‘ Transactions’ 
(1851). He named it Triplosporite ; thereby expressing its fossil 
state, the class or primary division to which it belonged, and its 
supposed peculiarity in structure. In regard to its affinities, he 
considered that it agreed in its scalariform vessels with all the fossil 
genera supposed to be acotyledonous, in the structure of its spo- 
rangia and spores with Lycopodiacee and Ophioglossee, and amongst 
fossils with Lepidostrobus, from which, however, it differed, accord- 
ing to Brongniart’s elaborate Memoir, which Mr. Brown accepted as 
accurate, in the manner of the attachment of the sporangium to its 
supporting scale. 
In 1848, Dr. Hooker published a valuable Essay on Lepido- 
strobus, in part ii. of the 2nd volume of the ‘ Memoirs of the 
Geological Survey of Great Britain’ (p. 440). From the examina- 
tion of a large series of sections from different cones, he made out 
their structure, and the nature and contents of the sporangia, and 
thus independently confirmed what Brown had determined from a 
single cone. He further showed that Brongniart’s notion that the 
sporangium was borne on the under part of the scale was incorrect, 
and so set aside the most remarkable difference between Brown’s 
Lriplosporite and Lepidostrobus. In anote appended by Brown to 
