248 Transactions. 



that no change had taken place. Attempts to oxidize the pigment with 

 potassium ferricyanide, with aqua regia, and with pure nitric acid left the 

 pigment apparently unchanged. Reduction with ammonium sulphide and 

 with sulphurous acid had a similar non-effect. The pigment is stable to 

 acids — strong hydrochloric — and to alkalies, standing boiling with watery 

 potash, but broken up by boiling with alcoholic potash. 

 :-A Though these chemical results are negative on the whole, yet they serve 

 to distinguish the pigment from all the known haemoglobin compounds. 



It was considered possible that more than one pigment was present, 

 and efforts were made to effect a separation. Extracts made with hot 

 alcohol precipitate on cooling. Both residue and filtrate contain pigment, 

 but with the same bands. If an ethereal extract be evaporated down 

 almost to dryness, and then taken up with an equal amount of absolute 

 alcohol, the same bands are seen as in the original ether solution. The 

 residue, insoluble in the alcohol, gives in ether solution the same series of 

 bands, and with the same relative proportion of depth. The ethereal solu- 

 tion of the pigment is greenish-yellow in colour, not fluorescent. 



The pigments already recorded* in Mollusca are haemoglobin, haematin, 

 haematoporphyrin, and biliverdin. The ready solubility in ether of the pre- 

 sent pigment excludes all four of these ; its speGtrum excludes all of them 

 except perhaps haematin, which, in acid solution, certainly has four bands, 

 but in the following positions : 1, between C and D ; 2, close to D; 

 3, between D and E ; 4, towards F. All but the first are lost in alkaline 

 solution of haematin. 



A second series of pigments recorded in Mollusca are those belonging 

 to the melanin group, to which this pigment certainly does not belong. 



The solubilities of this pigment in the fat-solvents would suggest rela- 

 tioaships to the lipochromes, a series of pigments associated with fats ; but 

 these are in general unstable, and all have but two bands, in the region 

 between the F and G lines. 



Art. XXXII. — Some Experiments on Tutin and Tutu Poisoning. 



By John Malcolm, M.D. 



[Read before the Otago Institute, 7th October, 1913.'] 



The following is a short description of some work on tutu and tutin poisoning 

 that has occupied me at various periods since the publication of the joint 

 paper on tutin by Dr. Fitchett and myself in the " Quarterly Journal of 

 Experimental Physiology " (vol. 2, p. 335, 1909). In the beginning of that 

 paper we gave the history of the previous work done on the subject, and 

 a practically similar account is also given by Dr. Fitchett in a paper pub- 

 lished in these Transactions (vol. 41, p. 286, 1909). 



Since the publication of these papers, a paper entitled " On the Toxi- 

 cology of the Tutu -plant " has been published by W. W. Ford in the " Journal 

 of Pharmacology and Therapeutics " (vol. 2, 1910). Dr. Ford had received 

 some tutin from Mr. Aston, Wellington, and had experimented in very 



* 0. v Fiirth, Vergleichende cheinische Phys. der niederen Tiere, pp. 527-33. 



