Chap. IX.] VAPOUR OF CHLOROFORM. 177 



good leaves was left for 25 m. under a receiver holding 19 oz. with 

 sixty minims of alcohol in a watch-glass. Xo movement ensued, 

 but some few of the glands were blackened and shrivelled, whilst 

 many became quite pale. These were scattered over all the leaves 

 in the most irregular manner, reminding me of the manner in 

 which the glands were affected by the vapour of carbonate of am- 

 monia. Immediately on the removal of the receiver particles of 

 raw meat were placed on many of the glands, those which re- 

 tained their proper colour being chiefly selected. But not a single 

 tentacle was inflected during the next 4 hrs. After the first 2 hi-s. 

 the glands on all the tentacles began to dry; and next morning, 

 after 22 hrs., all three leaves appeared almost dead, with their 

 glands dry; the tentacles on one leaf alone being partially in- 

 flected. 



A second plant was left for only 5 m. with some alcohol in a 

 watch-glass, under a 12-oz. receiver, and particles of meat were then 

 placed on tiie glands of several tentacles. After 10 m. some of 

 them began to curve inwards, and after 55 m. nearly all were con- 

 siderably inflected; but a few did not move. Some anaesthetic 

 effect is here probable, but by no means certain. A third plant 

 was also left for 5 m. under the same small vessel, with its whole 

 inner surface wetted with about a dozen drops of alcohol. Parti- 

 cles of meat were now placed on the glands of several tentacles, 

 some of which first began to move in 25 m.; after 40 m. most of 

 them were somewhat inflected, and after 1 .hr. 10 m. almost all 

 were considerably inflected. From their slow rate of movement 

 there can be no doubt that the glands of these tentacles had been 

 rendered insensible for a time by exposure during 5 m. to the 

 vapour of alcohol. 



Vapour of Chloroform. ^The action of this vapour on Drosei-a 

 is very variable, depending, I suppose, on the constitution or age of 

 the plant, or on some unknown condition. It sometimes causes 

 the tentacles to move with extraordinary rapidity, and sometimes 

 produces no such effect. The glands are sometimes rendered -for a 

 time insensible to the action of raw meat, but sometimes are not 

 thus affected, or in a very slight degree. A plant recovers from a 

 email dose, but is easily killed by a larger one. 



A plant was left for 30 m. under a bell-glass holding 19 fluid oz. 

 (539.9 c.c.) with eight drops of chloroform, and before the cover 

 was removed, most of the tentacles became much inflected, though 

 they did not reach the centre. After the cover was removed, bits 

 of meat were placed on the glands of several of the somewhat in- 

 curved tentacles; these glands were found much blackened after 

 6 hrs. 30 m., but no further movement ensued. After 24 hrs. the 

 leaves appeared almost dead. 



A smaller bell-glass, holding 12 fluid oz. (340.8 c.c), was now 

 employe<l, and a plant was left for 90 s. under it, with only two 

 drops of chloroform. Immediately on the removal of the glass all 

 the tentacles curved inwards so as to stand perpendicularly up; 

 and some of them could actually be seen moving with extraordi- 

 nary quickness by little starts, and therefore in an unnatural man- 



