Orlovich, Drinnan & Ladiges, Floral development in the Metrosideros group 
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at the outer edges (Fig. 7c). The stamen bundles thus fonued are clustered opposite each 
petal (Fig. 7d). The region of filament fusion in each bundle elongates (Fig. 7e) to 
produce a fascicle in the mature flower. In the mature bud, there is no obvious cleavage 
in the fascicle, however, there is a small gap at the centre of the tip of each fascicle 
indicating that stamens are not initiated first in this central position. Fascicles are situated 
on the rim of the hypanthium in the mature flower (Fig. 70 and have the same texture 
and colour as filament tissue rather than tissue derived from the hypanthium. 
Fig. 2. Floral development of Lophostemon confertus. a, young flower bud showing two large (Kl, 
K2) and three smaller sepal primordia. Two floral bracts (bud scales) have been removed (x 145); 
b, bud with sepals removed to show sequential initiation of the first few petal primordia (x 120); 
c, part of a flower bud showing two petal primordia (P). In front of each primordium is a swollen 
region, the pre-stammal bulge (PSB), upon which the stamens will develop (x 180); d, the petal 
primordium is clearly differentiated from the PSB, which has developed a shallow, vertical groove 
(arrow) (x 150); e, two adjacent petals and PSB. The left primordium is much larger than that on 
the right. Small swellings on the PSB beneath the left primonlium are individual stamen primordia; 
no stamen primordia have developed on the PSB on the right (x 95); f-i, initiation and development 
of stamen primordia on the PSB. Stamen primordia are first initiated along the lower central 
region and then along the top of the PSB. The groove extends back along the abaxial side of the 
fascicle (f x 110; g x 90; h x 68; i x 70). (a-h from AND 481; i from DAO 187). 
