THE CHAULMOOGRA TREE AND RELATED SPECIES. 25 
ing habit of chaulmoogra trees are not known, but the fact that 
the trees are polygamous may have something to do with this. The 
flowers are undoubtedly dependent on insects for pollination, and 
while it is said of the species of Hydnocarpus that male flowers with 
rudimentary ovaries and female flowers with regular stamens but 
without pollen occur at the same time with strictly male and female 
flowers, it must be stated that on the trees of Hydnocarpus anthel- 
minthica (in Bangkok) and of H. curtisii (in Penang) examined by 
the writer, only male flowers were found, and in the first species male 
flowers with a well-developed hirsute style. It may also be that 
this group of trees does not flower every year and that they are all 
biennial fruiters. It is well worth while to study these questions, 
as very little is known of the flowering habits of these trees ; in fact, 
the female flowers of Tarakatogenos kurzii have never been found. 
The remoteness from civilized centers of the forests where these 
trees occur, the danger and difficulty encountered in collecting the 
seeds (which may not be found every year), and also the conditions 
under which seeds are at present collected would point to the neces- 
sity of starting plantations of Taraktogenos kurzii, which is known 
to yield the true chaulmoogra oil, and also of such species of Tarak- 
togenos, Hydnocarpus, and Asteriastigma as yield oils of similar 
composition. This would assure a steady supply and a uniform 
crop and avoid the possibility of having several species confused, 
as undoubtedly is the case at present in certain localities. It has 
been stated by an eminent authority that owing to the very encour- 
aging work carried on in Hawaii and the great success achieved 
in the treatment of leprosy with chaulmoogra-oil derivatives, the 
lowest yearly demand will be for 1,000,000 liters of oil. The present 
output, the conditions under which the seeds are collected, and the un- 
certain fruiting periods of these species make it certain that the 
demand will far exceed the output. With this in view, the expe- 
dition was undertaken by the writer, of whose work this is a prelimi- 
nary report, for the purpose of securing viable seeds of as many 
species as possible, and these seeds are now growing in several places. 
(PL XVI.) 
The following suggestions are offered regarding the requirements 
for establishing plantations of Taraktogenos kurzii. The soil 
should be of a sandy nature, preferably quartz sand. Perfect drain- 
age is necessary, and undulating or hilly land is preferable. The 
region should have a distinct rainy season with a pronounced dry 
season in the winter months, but still with considerable humidity. 
The winter temperature should not fall below 40° F. The fore- 
going represent approximately the climatic and soil conditions of 
this species in its native habitat. Other species, such as Hydno- 
