FERTILISATION- OF SOME AUSTRALIAN PLANTS. 
405 
Castanospermum australe , A. Curin. ; Moreton Bay Chestnut or 
Bean Tree ; Order Leguminosse. 
Albizzia proccra , Be nth. ; Order Leguminosse. 
Eucalyptus platyphyUa , F. v. M., Poplar Gum ; Order Myrtaceze. 
SarcocepJialus cordatus , Miq., Leichhardt Tree; Order Rubiacese. 
Ficus colossea, F. v. M. ; F. Ounninghamii , Miq. ; Order Urticaeeie. 
3.— ON THE FERTILISATION OF SOME AUSTRALIAN PLANTS. 
(1 Plate.) 
By A. G. HAMILTON \ Public School, Mount Kcnibla, New South Wales. 
PITTOSPOREiE. 
Fittosporum undulatum , Andr. — In the majority of trees the 
dowers are proteraudrous, the anthers being well developed and full 
of good pollen. The dowers are very attractive to insects, from their 
powerful sweet scent and free secretion of nectar. But in a small- 
proportion of trees the anthers are small and short, and the pollen 
does not appear to be functional, in addition to which the anthers 
do not dehisce. . They are very closely ad pressed to the base of the 
ovulary, and secrete nectar. The dowers of this form are also sweet- 
scented. These short anthers vary much in size, even in the same 
dower, and I think it probable that the trees are in a state of transition 
towards separation of the sexes. As I stated in a note read before the 
Linnean Society of New South Wales in September, 1893, 1 have not 
been able to find any record of this ; but Mr. E. Betche, to whom I 
pointed out the circumstance, and who verified it by observation on 
the trees about Sydney, pointed out the following passage to me in 
Engler and PrantVs “Natiirliche Pdanzenfamilien” (1) : — u The Large 
coloured dowers (of Pittospomu), the sweet smell, and secretion of 
honey in many dowers 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 dowers of 
Fittosporum tenuif'olium are proterogynous, and that P. euyenioides 
inclines to separation of the sexes.” It is very interesting to have 
this confirmation ot* the facts above stated from New Zealand. 
The dowers of both forms are much frequented by bees, both 
native and introduced, and by butterdies, especially the Pieridm and 
Fapilio Madeayanus , 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. 
Citriobatus multi/torus , Cunn. — In this plant the anthers and 
stigma mature simultaneously, and this fact and the minute size and 
inconspicuous colour of the dowers indicate that it is self-fertilised, 
a view which would seem to be confirmed by the large number of 
dowers which develop fruits. But, on the other hand, the presence of 
nectar and the very sweet scent would point to the agency of insects. 
