of Bennettites gihsonianus , Carr . 44 1 
section of the embryo, divided into two halves by a usually 
very distinct line which coincides with the long axis of the 
ellipse, and is continued through its whole length. This line 
is the division between the two cotyledons. Where the 
section is not too oblique and the preservation is also good, 
six points may be seen in each cotyledon which form a 
median transverse row, and are undoubtedly the transverse 
sections of as many vascular bundles (Plate XXVI, Figs. 1-4). 
Carruthers had not noticed this remarkable state of preserva- 
tion of the embryo ; he saw the parenchyma in the inner body 
of the seed, but he took it for the endosperm, for he says on 
p. 6 98 : ‘ Enclosed by these envelopes is the nucleus, with its 
membranous covering, and abundant albumen. The sub- 
rectangular cells of the albumen are obvious in several 
specimens, but I have not hitherto detected the embryo.’ 
Nevertheless there is an indication at least of the embryo to 
be seen in the corresponding figure 1 ; a portion of the 
boundary line between the two cotyledons is given in the 
drawing, but it was probably taken for a merely accidental 
splitting. 
The embryo is surrounded by a thin membrane in the form 
of a brown line. In many cases the membrane lies immediately 
on the embryo, in others there is a fissure-like space between 
them filled with the material of petrifaction. We might be 
tempted to see in this interval (PI. XXVI, Figs. 2, 3) the trace 
of an endosperm which was present though in small quantity. 
But it is against this view, that the space in question is not 
found uniformly on all sides of the embryo, and further there 
is the important fact that a perfectly similar fissure is very 
often seen between the two cotyledons, where it can only be 
referred to shrinking. It must therefore be due probably to 
the same cause in the periphery, and we must suppose that 
the seed was without endosperm. As regards the brown in- 
vesting membrane, this appears usually as a simple line, its 
cellular structure has nowhere been demonstrated with any 
certainty ; but I have no doubt that it will be found to answer 
1 Figure 9 in pi. 59. 
