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and the valves themselves to be at once pericarp and style. It is not worth 

 entering into any discussion upon the reasonableness of such a supposition, 

 as it is not likely to find any advocates among botanists ; but I may observe, 

 that Amici's observations seem to shew that the 5 valves of the nucule, as 

 they are called, are a verticillus of leaves, straight at first, and twisted after- 

 wards; and that the nucule itself is, therefore, analogous to the bud of flower- 

 ing plants. 



The globule is described by Dr. Greville as " a minute round body, of a 

 reddish colour, composed externally of a number of triangular (always?) 

 scales, which separate and produce its dehiscence. The interior is filled 

 with a mass of elastic transversely undulate filaments. The scales are com- 

 posed of radiating hollow tubes, partly filled with minute coloured spherical 

 granules, which freely escape from the tubes when injured." Vaucher de- 

 scribes them as " tubercles formed externally of a reticulated transparent 

 membrane, containing, in the midst of a mucilaginous fluid, certain white 

 articulated transparent filaments, and some other cylindrical bodies, closed at 

 one end, and appearing to open at the other. These latter are filled with 

 the red matter to which the tubercles owe their colour, and which disappears 

 readily and long before the maturity of the nucule." The account of the 

 globule by Agardh is at variance with both these. " Their surface," he 

 remarks, " is hyaline, or colourless ; under this membrane is observed a red 

 and reticulated or cellular globe, which has not, however, always such an 

 appearance ; often, instead of this reticulated aspect, the globe is colourless, 

 but marked by rosettes or stars, the rays of which are red or lanceolate. 

 In the figures given by authors, one finds sometimes one of these forms, 

 sometimes the other. 1 have myself found them both on the same species ; 

 and I am disposed to believe that the last state is the true kernel of the glo- 

 bule, concealed under the reticulated scale. (When the globule is very ripe, 

 one may often succeed, by means of a slight degree of pressure, in sepa- 

 rating it into several valves, as is very well shewn in Wallroth's figures, 

 tab. 2. f. 3. and tab. 5. These valves are rayed, and no doubt answer to the 

 stars, of which mention has been made.) The kernel contains some very 

 singular filaments; they are simple (I once thought I saw them forked), 

 curved and interlaced, transparent and colourless, with transverse striae, 

 parallel and closely packed, as in an Oscillatoria or Nostoc ; but what is 

 very remarkable, they are attached, several together, to a particular organ 

 formed like a bell, which is itself also colourless, but filled with a red pig- 

 ment. This bell, to the base of which on the outside they are fixed, 

 difters a little in form in different species. It is slender and long in Chara 

 vulgaris, thicker in C. firraa, shorter in C. delicatula, and shorter still in 

 C. collabens. I have not succeeded in determining the exact position of 

 these bells in the kernel. I have often thought they were the same thing 

 as the rays of the rosettes or stars upon the globule above mentioned ; 

 whence it would follow that they are placed near the surface, while the fila- 

 ments have a direction towards the centre. The bells are not numerous; 

 they often separate from the filaments, and readily part with their pigment, 

 which renders it difficult to observe them, and has caused them to be over- 

 looked." That these globules, whatever their nature may be, have no sort 

 of analogy in structure with anthers, is clear from these descriptions, which- 

 ever may be eventually admitted. Wallroth, indeed, says he has sown 

 them, and that they have germinated; but this observation requires to be 

 verified. 



It does not appear from the preceding descriptions that Chara has a 

 marked affinity to any other plants. I incline to the opinion of those who 



