550 The Philippine Journal of Science ma 



and somewhat larger. The interior structure of the two seeds 

 is very similar; but, judging from our experience, Taraktogenos 

 kurzii becomes rancid rapidly, while Hydnocarpus wightiana 

 keeps well for years. Most of our supply of seed was obtained 

 through a Rangoon firm, probably from Chindwin Valley. 

 Other sources are Assam and Bengal. On account of the poor 

 keeping qualities of the seed, shipments from Chittagong (the 

 most important chaulmoogra oil center) are made chiefly in 

 the form of oil. 



EXTRACTION OF THE OILS 



The data on yield of oil, amount of shell, etc., of the ten 

 species are collected in Table 2, the items being as follows: 



Sample. — The samples are described in the previous section. 

 Usually a 2,000-gram sample was taken, which gave sufficient 

 oil for the distillation test. A larger sample of Pangium edule 

 was necessary. 



Estimated age. — The age alone does not determine the condi- 

 tion of the sample. Almost all of the samples were sundried 

 immediately after collection, but in many cases this was not 

 done with sufficient thoroughness. In the dry conditon all of 

 the seeds seem to be quite stable. 



Approximate weight— Usually twenty representative seeds 

 were chosen for this determination. Considerable variation in 

 size will be noted. The large seeds of the chaulmoogra group 

 are Hydnocarpus alcalae and H. woodii. Of these the former 

 has much the larger fruit. 



Shells of first- and second-grade seeds. — The basis of grading 

 is explained in the next paragraph. The weights of shells in 

 each grade are given because they show approximately the rel- 

 ative numbers of first- and second-grade seeds in the sample. 



First- and second-grade kernels. — Kernels which showed no 

 gross destruction by mold were considered first grade. Prob- 

 ably all of the kernels would have been of this grade if they 

 had been properly dried as soon as they became ripe. Such 

 kernels showed in general only slight signs of aging, but Tarak- 

 togenos kurzii kernels show a marked tendency to darken and 

 acquire a rancid odor, even though quite dry. Hydnocarpus 

 wightiana on the other hand, retains a fresh odor, taste, and 

 appearance for many months if kept fairly dry. 



The second-grade kernels were often almost totally destroyed 

 by mold, so that low yields of oil were obtained in cases where 

 a large proportion of the seeds had molded. 



