THE ORIGIN OF ANGIOSPERMS. 55 
microsporophylls have been shed, a large number of orthotropous seeds 
are found, mounted on long pedicels, arising directly from the axis. The 
seeds contain dicotyledonous embryos. Between the seeds, a still larger 
number of somewhat club-shaped organs, known as the interseminal scales, 
occur, also attached directly to the receptacle. —Distally these scales are 
all coherent by their apical margins, thus completely covering in the seeds, 
leaving, however, an orifice directly above each seed, through which the 
micropylar tube projects. Thus, in the fruiting stage, the interseminal scales 
form a complete investment or pericarp, and the whole of the macro- 
sporangiate portion of the cone appears to be of the nature of a single fruit. 
In figs. 2 and 3, the scale is too small to show the young seeds and interseminal 
scales clearly. Their position, however, lining the apical portion of the 
axis, is indicated. 
Further points in relation to the structure of the fructification of Bennettites 
will be discussed subsequently. We will, however, only add here that 
Wieland’s elucidation of the amphisporangiate cone of Bennettites has 
incidentally extended our knowledge of the earlier described genus William- 
sonia, in which the fructifications are borne on long peduncles, among the 
leaves forming the crown at the apex of the stem. It is possible that 
Williamsonia, in these features, is more primitive than Bennettites. 
Previous Interpretations of the Bennettitean Strobilus. 
Before beginning a discussion of the origin of the Angiospermez from 
ancestors nearly related to the Bennettitez, we would endeavour to make it 
clear that we do not consider any known member of the latter group to be 
exactly on the main line along which the Angiosperms have advanced. 
They, however, diverge so slightly, that we believe there is now little 
difficulty in perceiving how the Angiosperms may have originated. 
We may commence by considering the interpretations which have been 
arrived at with regard to the strobili of the known members of the group. 
In thus reviewing some of the earlier work, it must be remembered that, 
until recently, the evidence has been very incomplete. 
It is curious in this connection to find that in one of the earliest descrip- 
tions of the strobili of Williamsonia, read by Yates* before the Yorkshire 
Philosophical Society in 1847, the fructification was interpreted as consisting 
of “a number of scales, resembling sepals, petals, or perhaps dilated stamens, 
all growing from the top of the fruit-stalk, and overlapping one another.” 
Yates also points out how very different this cone is, both esternally and 
internally, from the flowers of the Cycads. 
Williamson t, working with very incomplete material of the genus William- 
sonia, distinguished two types of fructification as male and female, which he 
compared with the cones of living Cycads. Although we know now that this 
* Yates (1855) p. 40. t Williamson (1870) p. 672. 
