112 M. L. Garrcau on the Functions of 



do not anastomose ; and, during their continuance, these canals 

 are some of them stretched Hke rigid threads across the cell-cavity, 

 whilst others are. slack and more bulky. 



On my first observation of these currents, I speculated on the 

 causes of the movements ; but I might have probably ended with 

 the simple recognition of the fact of their existence, had not the 

 cause itself been unfolded to my observation, viz., the power of 

 contraction. On seeing this strange phenomenon, which I 

 looked upon for a long time with that restless curiosity which 

 astonishing and entirely unexpected circumstances produce in 

 the mind, I was disposed to attribute it to some illusion ; but at 

 length I was perforce obliged to yield to evidence obtained by ob- 

 servations repeated 500 times during a period of ten years, upon 

 the Salvia named and on very many other plants, and all of which 

 have led -to the same results. The contractions of the canals 

 usually proceed progressively, in such a manner that the granular 

 fluid is propelled gradually onwards — a dilatation larger or 

 smaller appearing in advance of the contracted portion, and pre- 

 ceding it, until the granules reach the nucleus, where their 

 course is arrested until they coalesce with it. In their progress 

 towards the nucleus, these dilatations are frequently retarded in 

 their course by the spots where anastomosing canals meet ; and 

 they do not reach the nucleus until after they have proceeded 

 upwards, downwards, or laterally, according to the disposition of 

 the anastomosing parts. Whilst these contractions continue, 

 the canal, contracted behind and much dilated in front, seems to 

 outstretch itself, and to be thrown into undulations or folds, 

 which are most numerous near the nucleus. It might be sup- 

 posed at first that, as is seen in most of the membranous pro- 

 cesses of the hairs of the pumpkin or gourd, and in those of 

 still very youn-g cells, the membraniform, soft, very extensible 

 material is a viscid matter which has an inherent motion towards 

 the nucleus ; but if we observe a canal having a direction 

 parallel to* the axis of the cell, and bearing an anastomotic 

 branch perpendicular to it, the latter is gradually pushed to- 

 wards the nucleus, forming a more and more acute angle ; and 

 when the contraction is past, as relaxation slowly succeeds, it is 

 seen to resume more or less closely its original relations, and 

 form anew a right angle to the canal it communicates with. 



Nevertheless, in citing this example, it is not my intention 

 to assert that the canals have a permanent fixed position ; for 

 this is not in accordance with fact, since we know that the 

 organic matter they are composed of is susceptible of movement 

 and of displacement. The distinguished observer Meyen seems 

 to have obtained the first perception of a portion of the move- 

 ments which take place in the living matter of cells ; but his 



