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Telopea Vol. 6(4): 1996 
The species exhibits a generalized pattern of development of monomorphic shoots 
with a 2/5 phyllotaxy in a counterclockwise spiral on which leaves and inflorescences 
develop coevally. Growth is anauxotelic and death of the apical meristem in wild 
populations is apparently seasonal. The apical meristems of plants in cultivation die 
sporadically, independent of season. The RGU (Fig. 1) consists of a number (m 
cultivation 6-15 or more) of sterile metamers followed by a number of fertile ones in 
which 1-4 axillary unit-inflorescences develop sequentially, at anthesis the 
inflorescence is a pseudoraceme of spikes. The plants exhibit late-suppressed 
hysteranthy (Grimes 1992). That is, the first-formed inflorescences are subtended by 
leaves, but the leaves subtending the inflorescences formed toward the end of the 
RGU are suppressed. 
The leaf-primordium forms alone on the apex (Fig. 2a), the stipules being produced 
on its flank during the second plastochron (Fig. 2b). The leaf-primordium grows 
very rapidly and by the fourth plastochron the apical bud is protected by a series of 
enlarged petiole-bases (Fig. 2c): that of the fourth leaf making up nearly 1/2 of the 
circumference of the bud. Intemode elongation starts between the fifth and sixth, or 
sixth and seventh plastochron. All metamers produce axillary buds in a biserial 
arrangement, and there is a temporal differentiation of the buds, those at the 
first-formed nodes of the RGU are vegetative, those at the later formed ones 
reproductive. In all cases the first bud to develop is sinistral to the mid-line of the 
leaf (Fig. 2c), and is first visible at the fourth (sometimes fifth) plastochron. 
Subsequently one or more buds might form in a biserial arrangement, and 
differentiation is basipetal. The buds resemble those of Lysilonin latisilicjuuvi (see 
below. Fig. 5b) and are made up of a reduced bract-like structure lateral to the 
bud-meristem. At older nodes of the RGU the first buds can develop sylleptically as 
a branch, but most of them remain dormant (Fig. 2d) and very poorly differenHated. 
Most branching is from proleptically developing buds. Toward the end of the 
formation of the RGU all buds form spicate unit-inflorescences. The sinistral 
first-formed bud differentiates before the second-formed one. The bud-meristem 
itself seems to develop into the unit-inflorescence (Fig. 3a) with no formation of 
vegetative metamers (cf. Lysiloma microphylhtm, below). 
Zapoteca tetragona (Willd.) H. Hern. (Figs 1, 3b,c) 
Zapoteca tetragona is widespread from central Mexico south along the Andean 
Cordillera from Venezuela to southern Ecuador. It is frequently cultivated. 
Observations were made over the course of two years on several specimens cultivated 
at the New York Botanical Garden. 
In most respects the pattern of growth resembles that of Paraserianthes lopbnntha. 
Differences are noted following. Shoots are monomorphic and in cultivation at least 
auxotelic (Fig. 1). The RGU consists of a series of ± 3-9 sterile metamers consisting 
of leaves, stipules, and axillary buds, and ± 3-? reproductive ones in which some of 
the axillary buds develop sylleptically into unit-inflorescences. There is no apparent 
modification of a resting bud, and while the plants grew faster during some times 
of the year than others, no period of real dormancy was noted. In contrast to 
P. lophantha, phyllotaxy is distichous at inception (Fig. 3b), though on plagiotropic 
shoots the leaves are displaced somewhat toward the upper side, so that the angle 
between them is about 160°. The stipules develop on the apex with, or even slightly 
before, the leaf-primordium, and by the second or third plastochron become much 
larger than the associated leaf-primordium. The growing buds, though enclosed in 
a envelope of precociously developed stipules, are not, as mistakenly stated by 
Grimes (1995, in data set), preformed. Axillary buds start to develop during 
plastochron four or five, and form an obconical bud lacking bracts or scales (Fig. 3c). 
The first bud is sinistral, subsequent buds form in a multiple biserial series as in 
