510 Ber ridge.- —The Structure of the Flower of 
his Systematic Botany, works out this theory in fuller detail, and grapples 
with the difficulty of deriving the bisexual flowers from the simpler unisexual 
forms ; his solution, however, is based on the hypothesis that the flower is 
a reduced inflorescence, and if applied to such a case as Castanea would 
involve a most intricate series of reductions and modifications to account 
for the varying and elaborate character of the epigynous, multipartite 
flower. 
A modification of this view has been recently brought forward by 
Lignier (15), who, after giving a minute description of the anatomy of the 
flower of W elwitschia , concludes that the Gnetales are very primitive Angio- 
sperms, and that they form the starting-point of a phylogenetic series 
which contains the amentiferous alliances, this series being parallel to that 
to which the main body of Angiosperms belongs. 
On the other hand, for morphological reasons, Prantl (20) looks upon 
the Fagaceae and Betulaceae as derived by reduction from plants bearing 
bisexual flowers possessing a perianth, multilocular ovary, and suspended 
ovules, but he considers that the two families have been developed inde- 
pendently, the Fagaceae being the more primitive of the two. 
Goebel (11) and Arber and Parkin (1) also regard the Fagales and 
Juglandales as reduced forms, the latter pointing out that the superior 
gamophyllous perianth, syncarpous ovary, and complicated inflorescence 
are not features likely to be characteristic of a primitive family. 
Van Tieghem (24, 25) was the first to show that the floral anatomy of 
Juglans and of the Coryleae was similar to that of the higher Angiosperms ; 
this conclusion was opposed by Nicoloff (10), who emphasized certain 
details in the structure of the flower of Juglans, on which he based his view 
that the ovule in this genus was axial and not appendicular ; finally Benson 
and Welsford (5), in a more recent study of the same and allied genera, 
confirmed Van Tieghem’s view, and showed that the placental bundles 
arise from the carpellary traces. The observations of Nicoloff, however, 
are of interest as indicating an essential likeness in the structure of the 
flower in Juglans and in the Fagaceae, which will be more fully dealt with 
in another part of this paper. 
Quite recently the view that the Cupuliferae are a primitive family 
has received support from the study of the structure of the foliar rays 
of the wood by several American observers. No high degree of primitive- 
ness, however, is here claimed for the Amentiferae, but only a degree 
relative to other Angiosperms, which would be quite consistent with the 
derivation of the group from bisexual flowering plants also possessing 
somewhat primitive characteristics, for a similar early type of wood structure 
is said to occur also in the Ericaceae and Platanaceae (22, 2), and in 
certain shrubby Rosaceae (7). 
None of the writers who regard the Amentiferae as derived from 
