On the Anatomy of Vegetables. 1 77 



fir it is impregnated with a refmous liquor ; in the vine, 

 efpecially at the time of the Cap, it abounds with an aqueous 

 fluid. 



The embryo, ftill inclofed in its teguments, has few or no 

 fmall tubes : all its parts are foft or almoft mucilaginous. 

 This tiffue is never found but in the expanded plant. It is 

 cbferved in the centre or at the circumference of the rami- 

 fications of certain ramified lichens, and in the ftems of mofs : 

 in monocotyledons, this tiffue diftributed around the large 

 tubes forms the ligneous filaments ; in dicotyledons, placed 

 around the pith, and the large furrounding tubes, it forms 

 ihe ligneous ftrata. The fmall and large tubes are generally 

 united : the exigence of the former depends on the prefence 

 of the latter. The bond which connects them is nothing 

 elfe than that which unites the effect to the caufe. Large 

 tubes, however, are fometimes found without the fmall, and 

 the fmall without the large; but it is to be recollected that 

 the latter are the creative organ, and consequently their exift- 

 ence is independent of that of the others. So much for the 

 tirft cafe. And it mull be confidered that there is an epoch 

 for many vegetables at which the large tubes are filled up 

 with the tiffue to which they gave birth. So much for the 

 iecond cafe. 



The prominent parts of the grooves and ftriae which cover 

 ■the furface of the vegetables are bundles of fmall tubes. This 

 tiffue is obferved alio in the mod delicate ribs of the leaves 

 and petals: it penetrates the ftamina and piftils, and reaches 

 to the extremity of the iiigmata; but in thefe delicate organs 

 it lofes its rigidity, and is nothing but cellular tiilue very- 

 much elongated. 



Chap. V. 



Of Lacuna. 



Nature, which effects expanfion without violence, and 

 which conducts organized beings, by infenlible gradations, 

 from non-exif^nce to life, and from life to death, teems here 

 to deviate from her ufual progrefs : flie deftroys to create, and 

 from the annihilation of organs gives birth to a new organic 

 fyftem. Lacuna? are regular and fvmmetric vacuities formed 

 in the interior of vegetables by the laceration of their mem- 

 branes. 



Lacunas, in general, exift only in plants, the tiffue of which 

 is foft. They are very numerous in mod of the aquatic herbs. 

 Thjey are, however, found fometimes in vigorous trees the 

 wood of which is very hard ; but in all cafes they are formed 

 only by the deltruction of the cellular tiffue, which is the 



weakeft 



