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Telopea Vol. 6(4): 1996 
Discussion 
The basic pattern of flower development is essentially the same for all taxa studied 
here, and is similar to that described for other genera of Myrtaceae (Payer 1857, Leins 
1965, Mayr 1969, Bunniger 1972, Drinnan & Ladiges 1988, 1989a,b,c, 1991a,b, Ronse 
Decraene & Smets 1991). The flower apical meristem is convex only until the first 
couple of sepal primordia are initiated, after which it becomes prominently invagina ted, 
and the subsequent perianth primordia form on the steeply inclined wall of the 
developing floral tube. The first two sepals are positioned in a more or less opposite 
pair in the median plane (decussate to the floral prophylls), but spiral phyllotaxy is 
quickly attained and continued into the corolla. The order of initiation of the floral 
organs does not follow a strict centripetal order in any of the flowers examined; sepals 
and petals are formed in order, but the first signs of the gynoecium are apparent 
before the inception of stamen primordia. Stamen primordia are inserted in the 
Fig. 16. Floral development in Lysicarpus aiigustifolius. a, young half flower bud showing petal (P) 
and stamen primordia. The first stamens are initiated between the petals. Later primordia are 
initiated lower down on the hypanthium and are antepetalous (x 200); b, part of a more mature 
flower bud showing the long stamen filaments of the outer whorl (x 90); c, mature flower bud 
with sepals and petals removed showing the outer whorl of stamen filaments covered in hairs 
(x 23); d, flower bud of a similar age to that in (c) with the outer whorl of stamens removed. The 
inner stamens are grouped into antepetalous bundles (x 23). (from PGW 569). 
