500 
Stiles . — The Podocarpeae . 
of the ovule in Dacrydium cupressinum on the epimatium, which is here 
developed to a greater extent than the megasporophyll, are very suggestive 
of a possible origin of the ovuliferous scale in the Abietineae. If the 
epimatium of Dacrydium cupressinum is called an ovuliferous scale we 
practically have the state of affairs in the Abietineae. It is, of course, not 
by any means suggested that Pinus is descended from Dacrydium t nor 
for that matter that any of the Abietineae have descended from any of 
the Podocarpeae, or indeed any living Coniferous group from any other as 
we know them, but Dacrydium and Pinus may have inherited the same 
potentialities from the same ancestor. These considerations thus suggest 
that the Abietineae have sprung from the same primitive stock as the 
Podocarpean-Araucarian phylum, but in the respects mentioned above have 
developed much further from their common ancestors than the Podocarpeae, 
while in the formation of perfect cones they have retained a primitive 
character lost in the more recent Podocarpean genera, but still present in 
the more primitive members of the order. 
The point of view taken in the preceding paragraph involves the 
derivation of the complicated ovulate structure of the Abietineae from a 
simple sporophyll. This is, however, not at all a generally accepted 
hypothesis, for many botanists have thought that the simple cone scale has 
been derived by reduction from the more complicated double structure. 
The view that the single cone scale groups have been derived from 
ancestors essentially resembling the existing Abietineae depends for its 
support largely on abnormalities, and on the vascular structure of the cone 
scales. The abnormalities consist mostly of structures sometimes found in 
members of the Abietineae in which the normal cone scale is replaced by 
a bract bearing in its axil a structure more or less like the short shoot of 
Pinus} From this it has been argued that the double cone scale of the 
Abietineae is to be regarded as derived from the fertile equivalent of such 
a brachyblast shoot, and various well-known modifications of this view have 
been put forward . 2 But abnormalities, especially when they are supposed 
to be more or less of the nature of reversions, afford by themselves unsatis- 
factory evidence of phylogeny. As to the evidence of the vascular supply 
of the cone scales, this depends on the fact that in all groups of Conifers 
there is inverse orientation of the ovular supply as compared with the lower 
series of bundles serving the sporophyll (or the lower { bract ’ scale in the 
case of the Abietineae). In most cases the ovular supply and sporophyll 
supply are independent of one another from the cone axis. These facts 
are supposed to point to the double nature of the apparently single cone 
scales of the Araucarieae and Podocarpeae, the two scales as we have them 
in the Abietineae being very closely fused together. The opinion that the 
facts do not point to this conclusion in the Araucarieae and Podocarpeae 
1 See Coulter and Chamberlain (’10), p. 245 et seq. 2 See Worsdell (’00), p. 39. 
