566 Proceedings. 



known as " corkwood," on account of the exceptional lightness of the 

 wood, which, because of this quality, was used by the natives for floats. 



2. " Studies on the Chemistry of the New Zealand Flora : 

 Part II., the Karaka-nut," by Professor Easterfield and Mr. 

 B. C. Aston. [Transactions, p. 495.) 



Twenty years ago, said Professor Easterfield, the late Mr. W. Skey, 

 in the intervals of his official duties, pursued some investigations into 

 this subject, and succeeded in isolating a white bitter substance, in- 

 tensely pois< nous, to which he gave the name " karakin." The quantity 

 obtained was too minute to allow of thorough investigation, and Mr. 

 Skey's results could therefore be accepted only as provisional. The 

 melting-point of the substance was below, 212°Fahr.,or the heat of boiling 

 water, and it was described as containing no nitrogen. He had begun 

 the investigation de novo, and, though Mr. Skey had done excellent 

 pioneer woik, further investigation did not bear out all his conclusions. 

 The karaka {Corynocarpus) was a tree well known throughout New Zea- 

 land. It was also found in some of the other islands of the Pacific, 

 notably at the Chatbams, where it was abundant, and on account of the 

 absence of timber was an important tree — so much so that it was cus- 

 tomary to inscribe symbols of ownership on the bark. A trunk in the 

 Museum now had a mark of this kind, supposed to he a " portrait " of 

 the former proprietor. The wood, however, was of little use as timber. 

 One point he had been unable to ascertain, and he hi ped that inquiries, 

 if necessary, would be made and definite information obtained while a 

 remnant of the Moriori people of the Chatbams still survived — did they, 

 like ih< Maoti, pre par* the kernel and use it as an article of food ? The 

 fruit of the karaka was a b< rry, the pulp of which some people esteemed. 

 To him its taste was objectionable— suggestive of decayed dates. Within 

 was a thin shell, encb s ng a kernel possessing the qualities of a nut, and 

 from which could be obtained a thick oil. [The oil. which was shown, 

 was of a very dark-brown colour, and so thick as to appear almost solid, 

 scarceh moving though the hottle was inverted.] This oil contained 

 oleine and yielded oleic acid. The thickness of the oil was due to its asso- 

 ciation witli vtgeiable wax. [The wax, pure white, was shown separately.] 

 Th poison did not leside in the oil, wiiich was innocuous, bad no bitter 

 taste, and was just such as mipht be found in any of the sweet nuts. To 

 pre pate the kernels for food the Maoris first cooked the berries, whioh 

 would have the effect of loosening the textures of the kernel and render- 

 ing it more accessible to the wattr in which it was afterwards soaked for 

 aptn d varying from a few days to some weeks, when the po sonous 

 constituents had disapj eared. Mr. Skey, finding that the extract from 

 the berries heaied to boiling-point lost its bitter taste, inferred that the 

 co< king was sufficient, without the subsequent pn cess, to render the 

 ktrnel non-poisonous. But he (the professi r) found that if the nut was 

 boiled in water prussio acid was given off. Now, only two other similar 

 cases were known, and the only known substance yielding prussicacid by 

 decomposition in this way was amjgdaline, found in bitter almonds, 

 peach and cherry kirnels, &o. ft seemed reasonable to infer that the 

 karnka contained amygdaiine or seme analogous substance which by 

 decomposition jieldid { russic acid and a specific poison, while there 

 was the alternative pi ssibility that the poisonous effect of the kernel 

 was due only to the prussic acid. There was another point of re- 

 semblai ce to the almond. From the original solution in water ether 

 removed piactically nothing, but if the solution was boiled and the 

 prussic acid drivm off thm ether became effective as a solvent. 

 Amygdaiine isolatid was not poisonous. It was found associated in 

 the almond with a sudstance known as "emulsin," a kind of fer- 

 ment olosely allied to diastase, and to certain digestive ferments pro- 



