OF THE FOSSIL PLANTS OF THE COAL-MEASUKES. 
13 
approaches nearest to Cokda’s Psaronius radiatus ; but it differs wholly from that plant 
in the cellular hairs with which its roots are clothed. The only plant which Cokda has 
described in which the roots are similarly furnished is his Protopteris Cottai ; but in 
that plant the sclerenchymatous cylinder of each root is invested by a thick composite 
layer of parenchymatous cells, whereas in my plant the hairs spring abruptly from the 
exterior of the sclerenchymatous cylinder. As this appears to be an undescribed 
species, I may be permitted to dedicate it to my friend Professor Renault, from whose 
labours amongst the fossil plants of Autun so much good has already arisen, and is 
likely yet further to arise. Our investigations, proceeding side by side, mutually 
illustrate each other, and will eventually afford the means of establishing some 
trustworthy comparisons of the flora of the French coal-field with that of Lancashire. 
I propose to designate my plant the Psaronius Benaultii. It is of course possible that 
it may some day be proved to be the base of a Caulopteris, or some other of the supposed 
tree ferns whose stems have already been discovered in the Coal-measures. 
The next plant which I propose to describe is one of the most remarkable as well 
as the most beautiful of those which I have met with in our Lancashire deposits. On 
the first glance at its structure we might suppose the Carboniferous forests to have been 
hung with Bignoniaceous Llianos like those of Brazil ; but closer examination demon- 
strates that this resemblance is only a superficial one. At the same time a remarkable 
instance is furnished by this plant of those resemblances between very different objects 
that have of late years attracted the attention of botanists. Figs. 23-26, 32, 33, 34, 37, 
and 38 show the vascular portions of the stem arranged usually in six, but, in the case 
of the two last-named figures, respectively in five and four wedges, separated by corre- 
sponding inward prolongations of the cortical tissues — a condition which forcibly reminds 
the botanist of similar transverse sections of the stems of Bignoniacese. But further 
examination shows that my fossils are very different from that recent type, since their 
central axis is, like that of some of the arborescent Lycopodiacese which I have already 
described, composed of a mass of vessels. This axis forms the nave-like centre from which 
the six large vascular wedges radiate like the spokes of a wheel, each of these primary 
wedges being separated by medullary rays into a multitude of secondary ones. The bark 
is differentiated into several distinct portions, and the whole structure is invested by the 
double row of vertically elongated cells indicated by the letter Tc in each of the figs. 23, 
24, 25, 28, & 36. That the six radiating primary wedges are the products of exogenous 
growth is clearly shown by the sections of young twigs represented by figs. 24 & 25, 
in which specimens the central vascular axes alone exist — a condition of things 
reminding us strongly of what I have already described in the stems and twigs of 
Asterophyllites , and of some of the Lepidodendroid plants. I think there can be no 
doubt but that, as in the case of the triangular axial bundle of Asterophyllites , each of 
the hexagonal ones of figs. 24 & 25' represents the axial bundle of a young twig, and 
that the radiating vascular laminae constituting the six primary wedges are the results 
of exogenous processes of growth, which have converted leafy twigs or branches into 
matured stems. 
