Douglas, Inflorescence development in Carnarvonia 
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a single flower (Fig. 1, 11). Most axillary subunits are anthotelic or determinate, 
having a terminal flower (Figs 3, 7). Other flowers along the axis are subtended by 
a bract (Fig. 4). In most material examined, the terminal portion of the primary or 
main axis appeared to senesce. 
The pedicellate flowers are actinomorphic, the four free tepals reflexing equally at 
anthesis (Figs 3, 7,12). Each epitepalous stamen filament is adnate to the lower half 
of a tepal. The distal half of each filament is free and stands slightly erect at anthesis. 
The filament is basifixed to the introrse anthers and there is a small connective 
protrusion distal to the microsporangia. In most cases, at anthesis, the pollen was 
contained within the anthers. In some cases, pollen was deposited around the distal 
end of the tapering style, proximal to the punctate and papillate stigma, although 
there are no morphological specializations of the style into a pollen-presenter. The 
mechanism of pollen adhesion around the style is unknown although pollen grains 
appeared to stick together at the apertures. The style broadens towards a stipitate 
ovary with a slightly lobed suture line. There are no hypogynous glands in the floral 
receptacle. Glandular trichomes line the claw of each tepal and fused filament and 
are composed of a basal tapered stalk and a globose end. An oily substance is 
exuded and the flowers have a strong 'Passionfruit fragrance' (P. Weston, pers. com.). 
Inflorescence topography/ontogeny 
Early ontogenetic stages of inflorescence and floral development are concealed by 
precocious trichome development. The anauxotelic portion of the inflorescence 
maintains a 2:5 phyllotaxis (Fig. 14) as is found in the vegetative axis. Transitory 
stages between vegetative and inflorescence apices were not examined. 
At the base of each lateral inflorescence axis or subunit composed of more than three 
flowers, just above the point of axis insertion in the leaf axil (Fig. 11), there is a 
single bract (a-phyll) normal to the median sagittal plane of the axis (Figs 8-10,13). 
Within each a-phyll axil there can be a flower, a small inflorescence or a senesced 
meristem. Developmental studies demonstrate that the a-phyll of the first metamer 
is persistent. The a-phyll can be positioned on the left (Fig. 17) or right side (Fig. 18) 
of the axis in relation to the subtending leaf primordium depending on the 
inflorescence. In some two-flowered and single flowered systems, there is no evidence 
of an a-phyll. The initiation of primordia and development of inflorescences in 
Carmrvoma is relatively similar for each axillary meristem or subunit. Below is a 
descriptive ontogeny of the inflorescence relative to the enlargement and development 
of subunits with deviations cited as appropriate. 
An axillary meristem (subunit meristem) is initiated within a leaf- or leaf-homologue- 
axil from the primary axis. The meristem enlarges and becomes slightly oblate although 
relatively flat (Figs 14-16). The first primordium or a-phyll, is initiated from the lower 
flank of the meristem in a transverse position relative to the leaf (Fig. 17). On different 
inflorescences the a-phyll varies between the left (Fig. 17) or right side (Fig. 18). 
Trichomes differentiate at the tip of the enlarging a-phyll primordium (Fig. 18-19). 
The second primordium, the p-phyll, is initiated from the opposite side of the meristem, 
approximately 180 degrees from the a-phyll (Figs 19-20). During the initiation of the 
p-phyll, there is slight elongation/differentiation of the internode between the a- and 
P-phyll (mesopodium) as evidenced by the restrictive trichome development and the 
lateral displacement of the a-phyll from the subunit-axis (Figs 21-22). As the subunit 
inflorescence apex enlarges and prior to and during the initiation of the y-phyll, a 
meristem can enlarge in the axil of the a-phyll (Figs 22, 23). There is variation in 
extent of axillary meristem enlargement in the a-phyll (compare the similar 
developmental stages in Figs 22 and 23). Within the axils of a-phylls in the subunits 
