336 The Philippine Journal of Science «m 



typified of course by Balsamo citrus. The genera of the Balsamo- 

 citrinae are very different from each other and have many dis- 

 tinct characters of taxonomic importance. In other words they 

 seem like the widely scattered survivors of a once larger group. 



Subtribe BALSAMOCITRINAE Swingle 



The genera of this subtribe fall into three divisions or super- 

 genera: (1) Aegle, Balsamocitrus, and Aeglopsis, with very 

 hard-shelled fruits having many locules and trifoliolate or rarely 

 unifoliolate leaves; (2) Feronia and Feroniella, with very hard- 

 shelled fruits with five locules coalescing into a single cavity, 

 and pinnate leaves; (3) Chaetospermum, with a leathery rinded 

 8- to 10-celled fruit and trifoliolate leaves. 



Recently a new member of the Balsamocitrinae has come to 

 light in the Malay Peninsula. It is apparently most closely 

 related to Chaetospermum but differs widely from it as will be 

 seen from the account given below. 



During the winter of 1917-18 Professor C. F. Baker sent to 

 me at Washington a fine specimen of the fruit of Murraya 

 caloxylon Ridl., 5 from a tree growing in the botanic gardens 

 at Singapore. It was at once apparent that this fruit did not 

 belong to a plant of the genus Murraya (Chalcas) but apper- 

 tained instead to the group mentioned above. As I did not have 

 a flowering specimen, I hesitated to publish on this plant because 

 it had so many aberrant characters that it seemed possible the 

 flower might show unexpected characters. 



Upon reaching Manila in July, 1918, I was agreeably sur- 

 prised to find that Professor E. D. Merrill, acting director of 

 the Bureau of Science, had secured from Mr. I. H. Burkill, 

 director of the Singapore Botanic Gardens, a beautiful flowering 

 specimen collected in March, 1918, and also fresh fruits from 

 the same tree. One of these fruits had been kept in the refrig- 

 erator and was still fresh enough to be studied. 



In the meantime Professor C. F. Baker, dean of the College 

 of Agriculture of the University of the Philippines, had brought 

 seeds from Singapore and planted them in the college nurseries 

 at Los Baiios, Laguna Province, Luzon. These seedlings enabled 

 me to observe the germination characters. 



Thanks to all this material, as well as my notes on the type 

 material of the species (H. C. Robinson 55^8) which, through the 

 courtesy of Mr. E. G. Baker, I was able to study in the British 



8 Ridley, H. N., New or rare Malayan plants, Series IV, Journ. Straits 

 Branch Roy. As. Soc. 50 (1908) 111-114. 



