PAPERS READ IN SECTION B. 



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1.— thp: alkaloids of the PUKATEA (LAURELIA 



NOVAE— ZEALANDI.EJ. 

 By BERNARD CRACROFT ASTON, Chief Chemist, Department of A>jriculture,,N.Z. 



The pukatea is one of the most characteristic trees in swampy 

 forests of the North Island of New Zeakmd, but is rare and local in 

 the South Island. Mature trees are easily distinguished by the radiat- 

 ing buttresses at the foot of tlie tiamk, which are of considerable 

 size, sometimes doubling what would be the circumferance of the tree 

 without them. The pale, almost white, bark, and the aromatic odour 

 from the biiiised leaves or branchlets, constitute additional means'of 

 recognition. 



The tree, endemic to New Zealand, originally described by Allen 

 Cunningham as Laurelia, was subsequently referred by Hooker to 

 Atherosperma , but has now been replaced l)y Cheeseman in its oiiginal 

 genus belonging to the family Monimiacet^, the nearest ally being a 

 species of Laurelia, in Chili. According to Colenso and T. Kirk, the 

 wood is soft, of great strength, extremely tough, does not split, allow- 

 ing nails to be driven in any direction, is difficult to burn, and is not 

 durable in contact wath the ground. The pukatea is among the largest 

 of New Zealand trees, sometimes reaching a height of 150 feet, and a 

 clear diameter of 5 to 7 feet, exclusive of the immensely wide but- 

 tresses at the base. The roots extend along the surface for a con- 

 siderable distance, those of a tree measured at Day's Bay being visible 

 for fully 50 feet. It is related that upon one occasion a man, being 

 •chased in the bush by a bull, tripped over some pukatea roots and lay 

 perfectly still, parallel and between two of them. The bull stood 

 poking, pawing, and snorting, for some time, and at length, finding 

 he could not come at his vis-a-vis, withdrew. In the Marlborough 

 *Sounds these trees attain enormous dimensions. In one instance 

 ■observed, a camp for fifteen men was made between two buttresses' of 

 .a pukatea. Colenso (p. .33, Essay, Vol.. I., Trans. N.Z. Inst., 1868) 

 states that the Maoris generally used tlie wood of the pukatea for the 

 ■carved figureheads of their canoes and for boat-building, it being 

 highlj'- sei-viceable for the bottom boards of boats, as in case of strik- 

 ing a rock only the spot so struck is staved. 



In the annual report of the New Zealand Department of Agri- 

 culture for 1901 (p. 284), attention was first drawn by the author to 

 the occurrence of alkaloids in the bark of the pukatea ; and the 

 peculiar property possessed by the bark when chewetl of causing a 

 tingling of the tongue — probably well known to bushmen and others 

 ere this — was traced to a crystalline alkaloid of definite melting point. 



The presence of alkaloids makes it extremely probable that the 

 tree contains medical properties of some value. The possibility of this 

 was recognisetl so long ago as 1868 by Colenso (Trans. N.Z. Inst., 

 1868, Essay, p. 51), who says that from the aromatic leaves and bark 

 of the pukatea a valuable essential oil might be extracted, seeing that 



