350 Transactions. 



P.M. 



8.20. Gill-movements have ceased in medium-sized fish ; heart-movement still visible. 



Large and small fish both deeply affected. 

 9.15. Large fish dead. Small fish deeply affected ; swimming upright, but very feebly, 



near surface. 

 Next day. Small fish apparently well. 



P.M. Exp. 114. 



3.55. Two cockles, of about the same size, were placed — one in sea-water, the other in 

 a 0-5-per-cent. solution of tutin in sea-water. Equal volumes of fluid were 

 used. 



4.0. The cockle in tutin solution has opened its shell. 



4.10. The cockle in sea-water has not moved. The one in tutin solution keeps opening 

 and closing its shell at intervals of a minute or two. 



4.15. Portion of the one in tutin solution is now extruded from its shell ; the shell 

 every now and then shuts down sharply, but without the extruded portion 

 being drawn back ; when touched with a needle the extruded portion is with- 

 drawn, but is pushed out again after a short interval. 



4.25. The one in tutin solution continues extruded, but withdraws when the glass 

 container is tapped with a pencil. 



Next da3^ 9 p.m. The one in tutin solution is dead ; throughout the day it has remained 

 with shell open and body extruded ; at noon to-day was alive, and withdrew 

 sluggishly when touched with a needle. The one "in sea-water is still alive, 

 with the shell firmly closed ; it has not been observed to open the shell through- 

 out the experiment ; on being ]ilaced in the tutin solution it opened its shell 

 in a few minutes, and behaved as the other had done. 



Exp. 115. 



Jan. 21. At 8 p.m. two flies — a large blowfly and an ordinary house-fly — were placed 

 in a cage with a watch-glass containing a solution of sugar in a 0-1-per-cent. 

 solution tutin. Both were observed to partake freely of the solution on 

 several occasions. 



,, " 22. At 8.30 p.m. both flies are active, and apparently quite normal ; they fre- 

 quently feed from the watch-glass. 



,, 23. At 12.15 p.m. the house-fly is dead. The blowfly is active, and apparently 

 normal. 



,, 24. Blowfly quite well ; allowed to escape. 



Exp. 116. 

 Mar. 1. About twenty house-flies were placed in each of two cages. Into one cage 



was put a solution of sugar in a 01-per-cent. solution tutin m normal saline; 



into the other a solution of sugar in normal saline. The flies, being thirsty, 



at once crowded rormd both watch-glasses, and partook freely. 

 ,, 4. All the flies are alive, and quite healthy. The flies with the tutin solution do 



not feed so readily as those with the normal saline ; they frequently approach 



the watch-glass, merely taste the solution, and retire ; now and again one 



will remain feeding. 

 ,, 7. Flies still all alive, and quite healthy ; diu'ing the week the solution has dried 



lip once or twice, and more 01-per-cent. solution tutui has been added. 



Despite the concentration by evaporation, they have displayed no symptoms. 



P.M. 



6.40. A few drops of 0-5-per-cent. solution tutin in distilled water added to the watch- 

 glass, which had become dry. 



7.0. On returning, found four flies on their backs, but not dead ; moving their lega 

 occasionally. Three other flies were affected. Every now and then wings 

 violently buzzed for a second or two, lifting flies on to tip-toes. They walk 

 rather incoordinately. 



7.5. One of the affected flies spinning round and round on its back, wings buzzing 

 continuously ; movement ceases for a short interval, and is then repeated. 



7.8. Both the other flies similarly affected. 



7.15. All three are now lying quiescent on backs, with occasional movements of legs. 

 Mar. 8. 



A.M. 



10.0. Ten flies dead ; several others seem unaffected. A large blowfly introduced 

 into the cage, and observed to drink the solution for 15 minutes. 



10.30. Blowfly not so active ; does not fly away when probed ; shows what seem to 

 be involuntary movements of the legs. 



