54 T raiiaactioiis. 



Dr. Treub, Director of the Royal Botanical Gardens at Buitenzorg, I have 

 been supplied Avith a sample of this resin, and have prepared podocarpic 

 acid from it. The acid agreed in all physical constants with the a6id from 

 kahikatea ; and the lower melting-point of podocarpic acid given by 

 ■Oudemans (188°-189°) is probably due to the difference in the conditions 

 luider which the determination was carried out. 



In the investigation of the miro and kahikatea I have been ably assisted 

 by Miss A. I. Slowey, M.A. 



(2a.) The Riniu (Dacrydium cupressinum) : (( Correction. 



The close resemblance between the acids of red and white pine has 

 ■caused Mr. Aston to re-examine the acid prepared from the former, which 

 was previously described under the name " rimuic acid " (Trans. N.Z. 

 Inst., 1903, vol. 36, p. 483). Careful comparison of the physical constants 

 and titration values has shown that podocarpic and rimuic acid are identical, 

 so that the latter name should be erased from chemical literature. At the 

 .same time it should be pointed out that the difference between the percent- 

 age composition of an acid of the formula Cj^HaoOg, ascribed to rimuic acid, 

 and the formula for podocarpic acid (Cj^H^gOa) is so small (0-6 per cent, 

 in the carbon and 0-3 per cent, in the hydrogen) that titration can alone 

 .settle the question of the correct formula. The titration values show with 

 certainty that Oudeman's formula is the correct one. 



It is not without interest that trees whose external characters have 

 led to the nomenclature Dacrydium cupressinum, Podocarpus cupressinus, 

 .and Podocarpus dacrydioides should be characterized by containing the 

 same acid, whilst this acid is absent in the other species of Podocarpus and 

 Dacrydium which have hitherto received the attention of the chemist. 



(3.) The Matai (Podocarpus spicatus). 

 (in conjunction with James Bee, M.A., M.Sc.) 

 In the matai (mai, or black-pine) heart-shakes are not nearly so common 

 ■or so large as in the rimu and kahikatea. When they do occur, however, 

 well-formed radiating groups of crystals may often be detected in the 

 yellow deposit within the cracks. It Avas expected that this material would 

 also be found to consist of podocarpic acid. The substance was found, 

 however, to be rather sparingly soluble in cold alcohol, whereas podocarpic 

 acid dissolves easily. From hot alcohol the substance separated on cooling 

 in crystals containing alcohol of crystallization, melting at 77°-78°, and 

 having the formula C^Q}i2oOQj^C2^rfi- After removing the alcohol of crystal- 

 lization the compound melts at 119*^, shows a specific rotation of -1-4-89°, 

 crystallizes from 60 per cent, acetic acid in large prisms, and is intensely 

 soluble in acetone, insoluble in light petroleum. The alcoholic solution 

 is coloured green by the addition of an aqueous solution of ferric chloride. 

 Upon distillation a strong smell of eugenol is produced. As regards chemical 

 constitution, two of the oxygen atoms are present as hydroxy groups and 

 two as methoxy groups ; the remaining pair is present as a lactone group ; 

 so that the formula may be rewritten CigHi2(OH)2(0 0113)2 CO 0-. The 

 compound yields well-characterized monacetyl, dibenzoyl, and sulphonic- 

 acid derivatives. Matai resinolic acid, CjfiHi.,(OH)o(6 CH.O.^COoH, has 

 also been prepared ; it crystallizes with 3 molecules of water of crystal- 

 lization, and is r(>converted to the lactone if boiled with water or by the 

 -action of cokl dilute niinci-al acids. 



