509 
Evolution of the Angiosperms. 
than usual. Not only are the fructifications of the Gnetales highly evolved 
structures, and far from primitive, — a conclusion which also points to the 
existence of the group in the past, — but the foliage of Gnetum , so Dicoty- 
ledonous in every respect, also strongly supports this view. Thus the 
leaves of past members of the Gnetales may have been already described, 
but confounded with those of Dicotyledons, and to this may possibly be 
due the paucity of fossil evidence of the former group. 
The Ancestors of the Gnetales. 
We may now consider the question how far the evidence will permit 
us to restore the past history of the Gnetales. 
The occurrence at the present time of three genera alone, one of which 
is monotypic and restricted in the highest degree as regards its distribution, 
and the fact that these genera, when compared, present such diverse features, 
are not in favour of the view that the group has had little or no past history. 
The facts are much more intelligible on the supposition that we are dealing 
here with three survivals of a group, which was once of considerable com- 
plexity but has now almost perished entirely. But a stronger argument, 
pointing in the same direction, is to be found in the interpretation of the 
Gnetalean fructifications advanced here. It has been shown that the 
application of the Strobilus Theory to these fructifications offers a simple 
explanation of their peculiarities. We have seen that on our view these 
may be regarded as reduced anthostrobili, derived originally from typical 
amphisporangiate pro-anthostrobili, with a well-marked perianth. A strong 
point in favour of this conclusion is that these reduced anthostrobili are 
aggregated into dense groups or ‘inflorescences’, which is exactly what 
we met with among certain Angiosperms, in which the strobili are much 
reduced. We are thus forced to conclude in favour of the first alternative 
outlined on p. 491, that the Gnetales were at one time a much diversified 
class of plants. 
The recognition of the fact that the Gnetalean fructifications may 
be interpreted as reduced anthostrobili affords one clue to the origin of the 
group. Another is to be found in the obvious relationship which exists 
between these plants and the Angiosperms. We have shown, in the 
historical sketch, that this affinity has been recognized from early times, 
and on many hands, though doubt and difference of opinion has existed as 
to whether these plants should not be included among the Dicotyledons, 
or even whether the Angiosperms were not derived from them. We have 
emphasized certain features connected with the fructifications, which 
strongly support the idea of the existence of a blood-relationship with 
the Angiosperms. There are, in addition, others of a vegetative nature, 
such as the very dicotyledonous-like foliage of Gnetum , and the mode 
Mma 
