NOTES ON DIPTEROCARPS.
No. 4. On the Embryo, Seedling and Position of the Flowers in various Species.
By I. H. Burkill.
This note deals, with the shape of the mature embryo, and with the characters of the seedling in a small number of species of the order Dipterocarpaceae: it deals also in a lesser measure with the position which the flowers assume when open. The observations were made and are recorded because it is believed that by a full knowledge of the morphology of the young plant, light will be cast upon the tangle which the genera of the order now present. In a lesser measure the position of the flower may possibly assist; and at any rate information concerning it is worth collecting.
Most of the facts in this note were got together by visits to Penang in the months of July, October and December, 1918: such as were not, are enumerated in the footnote* below. It happened that the year, 1918, was unusually favourable to the Dipterocarps in Penang, where almost every local species flowered and there Mr. Mohamed Haniff, of the Waterfall Gardens, observed and collected for me between my visits. To him for very much assistance, I tender my best thanks. I tender my best thanks, also, to Dr. F. W. Foxworthy, Mr. W. E. Kinsey and other Forest Officers for supplies of fresh seed from several parts of the Peninsula, which seed was put into cultivation in the Botanic Gardens, Singapore. No cultivation, however, returned the equivalent of days spent in the forests when the seeds were falling and germinating under natural conditions; for the seedling is so exacting in its demands that without experimenting on a very large scale cultivation often fails to supply adequate material.
The forest is undoubtedly the place in which to study the Dipterocarps. The earlier investigators were not able to realise that fully, not even collectively, and have left much to be done. The first of the workers worked, perforce, in European institutions remote from tropical nature, with material preserved by drying and chiefly collected by others. They constructed such classifi-
- ↑ The following list gives the names of the plants which were not studied in Penang, but in Singapore:
Shorea gratissima Dyer, S. leprosula Miq. Balanocarpus Zeilanjbus Thw., and Pachynocarpus Wallichii, King species wild or long established in the Botanic Gardens, Singapore. Hopea Mengarawan, Miq., wild in Singapore, island, Dipterocarpus cornutus, and Dyer, Hopea Curtisii, King, seeds grown from Penang Dipterocarpus crinitus, Dyer, D. grandiflorus, Blanco, D. Kerrii, King and Dryobalanops aromatica, Gaertn.f., seeds grown from Negri Sembilan.
Dipterocarpus Scortechinii, King, and D. sp. seads grown from Selangor.,
