3 1 8 Hartog . — On Br owned and Saraca. 
The presence of a complete or only partially reduced cycle 
of traces in the stipe of Proteaceae and Brownea would seem 
to favour the view that this is really the prolongation of the 
floral axis, and not a petiolar organ. 
All the evidence is consistent with the view that the flower- 
tube is a hypertrophy of the cortical zone of the axis through 
which the leaf-traces bend outwards to their leaves. 
In conclusion, we may note that this research, limited as its 
field has been, has shown the inadequacy of any single method 
or criterion of morphological research. I have striven to follow 
in the footsteps of our regretted master, Eichler, and to seek 
on every side evidence as to the modifications and filiation 
of structures which we are compelled to regard as having a 
common origin, and to reject all conclusions that ignore this 
necessary filiation. 
One word as to technique. For development I have worked 
mostly with the simple microscope and spear-headed needles, 
using sections of developing buds, and the compound micro- 
scope only to elucidate one or two difficulties, and especially 
to verify the exact phyllotaxis of the floral bracts. I have 
found a most useful adjunct to my outfit in Nobbe’s ger- 
minator, a thick block of porous pottery with a central disc 
surrounded by a gutter for water, and provided with a cover. 
On the disc the buds keep fresh for many days in a cool room ; 
and a bud half dissected at night has remained in good con- 
dition till next morning. The only necessary precaution is 
that the disc should not be wet, only damp, as wet accelerates 
the browning and softening of the flowers in their meristem 
state. 
The distribution of the vascular bundles has been chiefly 
worked out by moderately thick transverse sections treated with 
ammonia and glycerine, and sketched under the camera. For 
this purpose I have found the adjustable objective a* Zeiss 
invaluable. 
