252 Transactions. 



winking, and exaggerated respiratory movements ; within two hours all 

 these symptoms had disappeared, and at no time were they very pro- 

 nounced. The animal was fasting, and it may be that the tutin compound, 

 with the tissues, was dissociated in the stomach. This is the only experi- 

 ment that lends some support to Ford's results. 



Liver. — One experiment (No. 240) was done on tutin in the liver, with 

 negative results. 



Experiments on the Relative Toxicity of Two Varieties of Tutu. 



There is a general consensus of opinion among sheep-farmers that the 

 " fern " tutu (Coriaria angustissima) is more deadly than the ordinary 

 " tree " tutu (Coriaria ruscifolia). Ea'sterfield and Aston found that all 

 varieties of the plant contain tutin, and estimated the percentage in young 

 shoots of C. ruscifolia at 0-03, but no systematic quantitative estimation 

 of the amount of tutin in the different varieties has yet been made. 



The experiments which are described here were undertaken with the 

 view of comparing the toxicity of the varieties mentioned above, but I wish 

 to emphasize that this does not settle the practical question as to which 

 is the most deadly to stock, for the palatability and the ease with which 

 the plant may yield its poison are probably more important than slight 

 differences in the percentage of tutin present. 



Exp. 201 : A quantity (464 grm.) of C. ruscifolia leaves, stalks, and fruit 

 was gathered in the end of February. It was minced, covered with water, 

 allowed to steep for fourteen hours, and then pressed through flannel and 

 made up to 1,000 c.c. Of this fluid 50 c.c. per kilo administered by stomach- 

 tube to a rabbit (201) caused death with typical tutin symptoms in three 

 hours and three-quarters. From our former experiments, Fitchett and I 

 found that death resulted in rabbits from a dose of 6 to 8mlgrm. tutin 

 orally administered ; but there is, of course, the great probability that 

 in order to kill the animal more than that amount would be required when 

 the tutin is given mixed with the other extractives of the plant. The 

 experiment shows, however, that at least 0-03 per cent, tutin was present 

 (0"007 grm. in 50 c.c. = 0-14 grm. in 464 grm. of tutu = 0-03 per cent.). 



In March of the same year samples of two varieties of tutu were obtained 

 from the slopes of Swampy Hill, near Dunedin. The one variety was cer- 

 tainly C. ruscifolia, and from the descriptions given I believe the other 

 to have been C. angustissima. Each sample was extracted once, with water 

 as described above, and a few days later a second extract was made in the 

 same way, and the toxicity of the extracts determined on rabbits by oral 

 administration. 



The results were as follows : — 



Coriaria ruscifolia (80 grm.). 



First extract measured 1,8C0 c.c. (No. 212) 16 c.c. per kilo : no effect. 

 (No. 213) 40 c.c. per kilo : distinct symptoms ; recovered. (No. 214) 45 c.c. 

 per kilo : death in one hour and a half. Assuming that 45 c.c. of the extract 

 contains 0-008 grm., this gives 0-32 grm. tutin in the first extract. 



Second extract measured 1,150 c.c. (No. 210) 40 c.c. per kilo: gave 

 slight symptoms. (No. 215) 50 c.c. per kilo : caused death in three to 

 four hours. Assuming that 50 c.c. of this extract contains 0-008 grm., 

 the second extract contained 0-184 grm., or a total of 0-504 grm. tutu in 

 800 grm. tutu = 0"063 per cent. 



A third extract of the same material was made. It measured 1 ,000 c.c, 

 and of this 60 c.c. per kilo gave no symptoms. 



