Miscellaneous, 151 



those forming the middle of the wall between any two contiguous 

 channels ; they seem to be smaller and younger cells than the others. 



In all ordinary cases of cyclosis the motion is along the walls of 

 the cell, coming and going in paths which are, for the time at least, 

 permanent. But in the Saururus the granules lie in the centre of 

 the cells above described, and their motion is of a quite different 

 character. To those familiar with microscopic observations, we may 

 best describe this motion as perfectly identical with that seen in the 

 so-called vesicles in the ends of Closterium, which has been aptly 

 styled "swarming" by the English and Germans. The granules 

 are quite minute, rounded in form, and rather unequal in size. 

 Sometimes a cell is seen in which all motion has ceased ; in such 

 cases the granules are always closely crowded together in the centre 

 of the cell. 



The time during which this motion continues is quite remarkable. 

 Specimens of the plant kept for several days in water never fail to 

 show it ; while the proper pith-cells of all parts of the plant, even of 

 the blanched portions of the stem growing beneath the mud, seem 

 equally active. Indeed, no form of cyclosis, of which this is un- 

 doubtedly one, is so easily demonstrated. 



The nature of the granules, however, is not so readily determined ; 

 for they do not show the starch-reaction with tincture of iodine, 

 neither are they coloured as proteine-compounds (and such I had at 

 first supposed them to be) would be under this reagent. There is, 

 however, a remarkable difficulty, common also to many others, in 

 applying chemical tests to sections of this plant ; and this consists in 

 the rapid discoloration of the specimens, owing to the presence of 

 tannic acid, which acts upon the iron of the cutting instrument. It 

 is quite certain, however, that the granules are neither starch nor 

 proteine ; whether they are the so-called aleurone I am unable to say. 



To those familiar with the microscopic examination of freshwater 

 algae, this " swarming," apart from the best-known case of the 

 Closteriutn, must be quite familiar ; but such motions have always 

 been considered as in some way connected with sexual reproduction. 

 In the case in question, however, nothing of the kind can possibly 

 occur ; for the Saururus is, beyond a doubt, not only a phsenoga- 

 mous, but even a dicotyledonous plant, closely allied to the Pepper 

 family. The cells in which this motion is seen are evidently smaller 

 and younger than those in their immediate vicinity. Sometimes, 

 indeed, two vertical rows of small cells show the same motion. The 

 phenomenon in question would therefore merely indicate active cell- 

 multiplication, and not plant-reproduction, to which similar appear- 

 ances have always been referred. With a somewhat extensive 

 experience I am able to say that nothing of the kind has before been 

 observed in phsenogamous plants ; yet it must be admitted that one 

 single instance among them is sufficient to invalidate the inferences 

 formerly drawn from algae, as to the true meaning of this pecuUar 

 kind of motion. 



I am more earnestly disposed to insist upon this apparently ex- 

 ceptional case, because it confirms views long held and taught by 



