yS6 T hiselton-Dyer. — Morphological Notes. 
tion one would expect to find some trace of the seminiferous 
scale persisting, even' in the presence of an axillary bud. But 
it is clear that this is not the case. In the Abietineae with 
membranous cone-scales (possibly also in Sciadopitys ) it seems 
to me that the view of Von Mohl, supported by the researches 
of Stenzel, is probably correct, and that the seminiferous scale 
is complex in its origin. But I am not clear that this is the 
case when the cone is woody, as in Pinus. It does not follow 
because the seminiferous scale is replaceable by a fascicle of 
leaves that all potentially take part in its development. The 
general resemblance of a cone of Pinus to one, say, of 
Enceplialartos is obvious at a glance. In each case we have 
a ‘ carpophyll ’ enlarged above into an hexagonal apophysis 
with an ‘ umbo ’ on its external surface. However violent may 
seem the transformation, I have clearly demonstrated that the 
carpophyll in Enceplialartos is a modified leaf belonging to 
the primary axis: in the Abietineae it appears to me equally 
demonstrable that it belongs to a secondary one. As Van 
Tieghem has remarked : — 6 This establishes a fundamental 
distinction between Cycadeae and Coniferael But, as in 
Encephalartos , the umbo seems to me clearly the dilatation of 
the atrophied apex of a foliar organ. 
Returning to the specimen now described, I have already 
noticed that, unlike what takes place in the proliferous shoots 
of Larix , there is an abrupt discontinuity between the repro- 
ductive and vegetative regions of the axis. This reminds one 
in fact of Callistemon , where the same axis serves alternately 
one or the other purpose : an even closer analogy would be 
found in Cycas if the carpophylls were persistent. 
The explanation of the fact that a cone is not proliferous 
is to be found in physiological necessity. The upward stream 
of food is diverted and absorbed by the developing carpophylls, 
and the growing point of the cone is arrested in its further 
development practically by starvation. The upper semini- 
ferous scales share the same fate and become mere woody 
rudiments. Meanwhile the growth of the cone in diameter 
sets up a passive tension which would, by mechanical pressure, 
