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Observations of M. Raspail on the Chara mode of preparation. By 

 the late W. Griffith, Esq. F.L.S., 1833. 

 Take an internodus of Chara detached from the plant, and depriv- 

 ed of the branches which spring from the two opposite articulations, 

 by which the internodus is separated ; the bark which covers it may 

 be removed thus, the internodus is to be stretched out on a plate of 

 glass shorter than the space comprised between the two articula- 

 tions ; the glass is kept plunged in a shallow and small capsule 

 filled with water. Each shred of bark is. then to be pinched with the 

 point of a scalpel, proceeding from one end to the other, ayant 

 soin de ne pas penltrir trop avant. When all the shreds of bark 

 are removed, a cylinder incrusted with a white substance, adhering 

 strongly, hard and brittle, and resisting the action of the scalpels 

 makes its appearance. It consists of carbonate of lime, which must 

 be removed by a lame emoussee, by scraping the tube longitudinally. 

 If the tube thus prepared, be placed in the focus of a microscope and 

 plunged in water, these phenomena are observed. 



1 . A white mesian line is seen crossing obliquely two longitudinal 

 layers of a green colour, composed of longitudinal series of green 

 globules, the direction of which is parallel to the white line ; this 

 line extends itself on each opposite side of the tube. 



2. It is soon remarked that this white mesian line is a sort of 

 line of demarcation, between two currents proceeding in an inverse 

 direction, the course of which is marked by the hyaline masses which 

 they carry with them. One of these currents proceeds on the left of 

 the observer, the other on the right : but the globules of the one 

 do not mingle with those of the other. On the line of demarcation 

 large albuminous globules are sometimes visible, which obedient 

 to the effects of the two simultaneous and opposite forces of the two 

 currents revolve on their axes, being retained at the bottom of the 

 liquid by their specific gravity. 



Raspail placed two ligatures on the scraped tube £ of inch or 

 so from the articulation : the tube included in these ligatures was 

 detached from the plant. Not only did the circulation continue, but 

 even, in the space of some days the ligatures fell off, the ends of the 

 tube remained closed exactly by the union of their borders, and the 

 circulation continued to take place from the 26th July 1827 to the 

 3rd September of the same year. 



