56 



Dr. H. M. Kyle. On the Action of the [June 25, 



Table I. — Summary of Experiments which were made in order to 

 discover the Action of the Spurge-extract on Fishes and other 

 Animals. 



Strength and 

 nature of 

 solution. 



20 per cent, of 

 " fresh ex- 

 tract" ( = 0-2 

 per cent, of 

 tannin ap- 

 prox.) 



5 per cent, of 

 do. 



4 per cent, of 

 do. 



1 per cent, of 

 do. 



0*2 per cent, 

 of do. 



Period 

 within which 

 it is fatal. 



5 minutes 



10 to 30 

 minutes 



Animal 

 experi- 

 mented on. 



Trout 



and U 

 hours 



1 to 2 hour; 



'1 per cent. 1| to 2 hours ' 

 of do. 



*1 per cent. 2 to 4 hours 

 of do. alter 

 standing for 

 6 days 



0"05 per cent. ; 4 to 6 hours 

 of do. 



0*01 per cent. 4 to 6 hours 

 of do. 



0"2 per cent, of 2\ to 4 hours 

 " fresh ex- 

 tract " 



formed from 

 fruit and 

 leaves 



Do. 



]0to30 

 minutes 



Do. 



Do. 



Do. 



Do. 



Do. 



Do. 

 Do. 



Mode of 

 applica- 

 tion. 



Notes. 



Animals 

 immersed 

 in solu- 

 tion 



Do. 



Do. 



Do. 



Do. 



Do. 



Do. 



Do. 



Do. 

 Do. 



Control experiments per- 

 formed at same time. 

 Other trout immersed 

 in fresh water in vessel 

 of similar form. 



The variation in length 

 of period which proved 

 fatal was considerable. 

 This probably arose from 

 the condition of the ani- 

 mals when experimented 

 on. 



The symptoms were the 

 same in both strong and 

 weak solutions. In 50 

 per cent, of cases grea L . 

 excitement shown — the 

 fish darting about wildly 

 for some time, then rest- 

 ing exhausted, frequent- 

 ly in an inverted posi- 

 tion. Rate of breathing 

 increased, from 120 to 

 130 per minute — the 

 rate in control specimen 

 —to 140 to 160 per 

 minute. In 50 per cent, 

 of cases no excitement, 

 and animal remained in 

 normal position. Grulp- 

 ing movement of jaws at 

 intervals of 5 to 10 re- 

 spiratory movement;*, 

 accompanied, by jerking 

 movements of body. 

 Later, rate of breathing 

 became gradually slower. 



Loss of sensibility then 

 displayed. Grill -covers 

 held apart from pectoral 

 arch so that gills could 

 be seen during inspira- 

 tion. 



Roots seem to have more 

 of poisonous ingredients, 

 but these experiments 

 were performed early in 

 September, when stem 

 and leaves begin to lose 

 their sap. 



