432 BOTANICAL GAZETTE [DECEMBER 
obscure. While Scort, especially, as well as HALLrER, ARBER and 
PARKIN, BEssEy, and others, as well as myself, have all insistently 
urged that the path has thus really been blazed to a knowledge of 
the evolution of the angiosperm groups, no one has yet been ina 
position to bring the final methods more clearly into view. Now, 
however, I believe we can do so in the case of all but the extremely 
modified families, if not indeed ultimately in these too, by means of 
analogic methods combined with comparative morphology. 
We have seen how the staminate disk of Cycadeoidea ingens, and 
of all the other species so far known, bears inside the campanula or 
androecium many functional synangia on the raclhial axes, either 
inserted directly or on pinnules. Now we see, furthermore, that the 
campanula remains large in a form with greatly reduced fronds, 
while we may be sure that interiorly borne synangia are still present 
on the rachial axes, or at least may be in related forms, whether we 
can detect them or not. Whence it follows that a slight further 
continuance of the rachial reduction, so plainly under way, must 
result in a toothed campanula bearing interiorly on each axial or 
rachial line only a single pair of synangia and finally a single synan- 
gium and no more, just as diagrammatically shown in jig. 3. uch 
types we may call, because of the strictly convolvulaceous aspect, 
archaeosolandrous, arbitrarily dismissing for the present all mention 
of the central ovulate region to which we return below. 
Now plainly, having thus by a series of entirely simple stages 
reached this archaeosolandrous form, which we confidently believe 
will be detected in the fossil condition, it is only a minor step t0 
simpler types of pollen sacs, either borne in pairs or singly, and 
finally to elongations of the filaments suiting the requirements of 
such flowers as that of jig. 4, which is none other than a common 
morning glory, 
In short, the successive members of the series of steps outlined 
are these, letting capitals represent the known, and small letters the 
hypothetical plants: 
A’, Proangiosperms, or hemiangiosperms and pteridosperms. Pee 
A. The flower of Cycadeoidea dacotensis, with a campanulate disk of 18 bipin 
nate members 
B. The flower of C. ingens, with 12 bipinnate members. 
