OF THE FOSSIL PLANTS OF THE COAL-MEASTJEES. 
249 
Fig. 94 represents a lateral view of the finest specimen I have hitherto obtained from 
the Peel Delph. These Peel specimens usually resemble the nuts of the Salisburia sold 
in the grocer’s shops in China, but which are deprived of all their outermost sarcotesta. 
But the Peel specimens are even something more than this. There is no doubt that fig. 94 
represents a sandstone cast of the interior of the hard endotesta, with a thin film of tissue 
remaining upon the cast, and which, even in these sandstone specimens, retains superficial 
traces of the prosenchymatous structure of the endotesta, within which the cast was 
moulded. Such specimens do not, in any way, represent the external form of the seed, 
as will be shown in my description. The entire specimen in fig. 94. represents the exact 
form of the interior of the testa, the lower or tumid portion of it corresponding to the 
nucleus with its thin investing membranes, and the prolonged upper portion, with its 
three diminishing concave surfaces, of which only one appears in the figure, repre- 
senting the interior of an elongated micropyle. It is important that this fact should be 
correctly understood, since many of even the most recent references to these seeds are 
rendered erroneous by a confusion between their external contours and their internal 
casts. Thus Dr. Balfour describes T. olivceforme as “ an ovate, acuminate, three-ribbed, 
and striated fruit or seed ” (‘ Palaeontological Botany,’ p. 63), whereas it was twelve-ribbed, 
and we have no evidence whatever that its surface was striated. Professor Newberry 
figures a similar example to my fig. 94* *, of which he says that it “has suffered little 
injury beyond the loss of the fleshy envelope. In this and some others I have seen, the 
three conspicuous salient ridges which traverse the surface longitudinally are shown to 
be the remains of broad and delicate wings ; so delicate that they are generally all torn 
away with the exception of their thickened bases ”f. All this is, I am satisfied, a 
mistake, which so acute an observer as Professor Newberry would be one of the first 
to correct, after seeing my sections and specimens. In the valuable memoir published 
by Dr. Hooker and Mr. Binney the only sections figured are longitudinal ones. The 
publication in that memoir of figures of transverse sections would probably have 
prevented the perpetuation of these erroneous notions. 
I have not much to add to the descriptions of longitudinal sections of Trigonocarjpon 
published by these authors, except on one or two points on which fresh light is now 
thrown. Dr. Hooker and his coadjutor have described accurately the general features 
of these sections, including the two layers constituting the sarcotesta and endotesta. 
In their figures 7, 8, & 12 they also delineate the organ which apparently represents 
the lagenostome, but, as might be expected from the date of their publication, without 
recognizing its significance. 
longitudinal sections as possible out of one of them and of transverse ones out of the other. Out of the first of 
these, which was less than f of an inch in diameter, he obtained for me nine beautiful sections, and from the 
other, less than an inch in length, he obtained no less than eighteen equally fine transverse sections ! The 
more characteristic of each of these two series of sections have been figured in the accompanying Plates. 
* Report of the Geological Survey of Ohio, vol. i. Geology and Palaeontology, part ii. pi. 42. fig. 1. 
t Loc. cit. p. 366. 
