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probable that the trees are in a state of transition towards separation of the sexes. . . . Mr. E. Betche 
pointed out the following passage to me in Engler and Prantl's " Naturliche Pflanzenfaniilien " (1): " The 
large coloured flowers (of Pittosporese), the sweet smell, and secretion of honey ,in many flowers indicate 
fertilisation by insects ; but very few actual observations have been recorded. Mr. Thomson records, in 
Trans, and Proc. of the N.Z. Inst., 1880, that the flowers of Pittosporum tenuifolium are proterogynous, 
and that P. eugenioides inclines to separation of the sexes." It is very interesting to have this 
confirmation of the facts above stated from New Zealand. 
The flowers of both forms are much frequented by bees, both native and introduced, and by butter- 
flies, especially the Pieridse and Papilio Macleayanus, and fruit very freely. 
Fig. 1 shows the ordinary form of stamen and ovulary ; Fig. 2, stamens and ovulary in form, having 
short stamens ; while Fig. 3 is a semi-diagrammatic representation of a short stamen, showing the position 
of the pollen, which is undeveloped and abortive. 
3. A. G. Hamilton, in Proc. Linn. Soc. N.S.W., xxiii, 759 (1898), "Notes on 
the Fertilisation of Some Australian and Other Plants " Pittosporese. 
I have given an account -of the two forms of flowers noticed in this plant 1st, those with perfect 
stamens and pistils ; 2nd, those with perfect pistils, but having stamens very short and converted into 
nectaries, and not functional as pollen-bearers. Since then, I have seen a tree in Dr. Lee's garden in 
Wollongong, which sprang up as a seedling among ferns transplanted from the bush. In this tree the 
stamens are perfect, but the pistil is imperfect, and never sets seed. This completes the series of forms. 
T. Kirk (" Forest Flora of New Zealand," p. 81) says of Pittosporum eugenioides A. Cunn. : " In 
this species the flowers are in many specimens practically unisexual ; although both stamens and pistil 
are invariably present, one or other is abortive. The perfect stamens have longer and more slender 
filaments, and produce abundance of pollen; the imperfect stamens are carried on shorter, less slender 
filaments, and produce but little pollen. The pistil exhibits but little variation. Flowers with perfect 
and imperfect stamens may be produced on different trees, or both forms may be found on the same tree 
associated with perfect flowers; in the former case the trees are practically dioecious. Other New 
Zealand species of Pittosporum exhibit the same phenomenon." 
Pittosporum undulatum has manifestly reached a farther stage of differentiation, as the various 
forms are never found on one tree, so far as my experience extends ; the anthers in the second form are 
always quite abortive, having only a couple of dozen ill-formed pollen-grains in the sacs, which never open, 
and the anthers are mere honey-secretors. The filaments are very short, almost suppressed. 
In the other Illawarra species, P. revolutum Ait., I have never seen any approach to this state of 
affairs. All the flowers are perfect. 
4. " Notes on Variable dioacism in Pittosporum undulatum Andr.," with a plate- 
Thomas Steel, Proc. Linn. Soc. N.S.W., xxxvi, 329 (1911). 
Mr. Steel gives a useful bibliography of the observations of previous workers, 
and then proceeds : - 
Again, in 1902, Mr. R. H. Cambage (Proc. Linn. Soc. N.S.W., 1902, p. 593) brought evidence 
forward confirmatory of the observations made by the previously quoted botanists. During the last 
few years I have had opportunities of making close observations on several trees of P. undulatum growing 
in my garden, at Petersham, near Sydney, and on numerous others in gardens in the vicinity, which have 
yielded further information of an interesting nature. 
Usually towards the end of June, in the neighbourhood of Sydney, the flower-buds on the male or 
staminif.-r.nw" trees are well advanced, many of them being on the point of opening, while on the female 
or non-staniiniferons trees nothing but leaf-buds are visible. The blossoms on the latter begin to open 
iboiit tlir,-.- w,-ks or a month later than the others, and are accompanied by a succession of stammiferous 
flowers on tli- adjacent male trees during the whole period of flowering. The male trees are much 
handsomer than the female, because of the largor si of the blossoms and the bright yel 
anthers; while b.>th are fragrant, secrete nectar, and are freely visited by bees. 
