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244 NEW PUBLICATIONS.
3. That Mr. M'lror's plan of mossing is an important discoveiy in the di-
rection of intelligent culture.
4. That the renewal of tliC bark from the cambium leads to diifereut conclu-
sions as to the permanence of the supply of fresh bark, from those to be de-
duced from the theory of formation of the alkaloids in the leaves.
5. That no part of the tree— root, stem, or leaves—visited by the ascending
sap, seems to be the place of deposit of the alkaloids.
6. That these are formed in the cellular tissue of the bark, beginning from
the cambium outwards.
7. That the sources whence the materials are drawn for this elaboration are
at once the nourisliing sap descending in its usual course, and a lateral convey-
ance, through the medullary rays, of part of the deposit of the mother-substance
in the wood.
8. That inasmuch as this mother-substance is characteristic of the Cinchonse,
and is the source of the Cinchona-red, it may also mainly conduce to the for-
mation of the alkaloids, since it is probable that the characteristic principle of
each plant is originally one.
9. That the above jirinciple, deduced by M. Decaisne from his researches on
Madder, is equally true as to Eed bark.
10. That no explanation is at present offered of the tendency of the cells in
the root of the Madder to secrete the peculiar colouring-matter, nor in the
bark of the Cinchonse to produce alkaloid.
11. That the electro-chemical properties of the cells are nevertheless greatly
influenced by the respiration, and that by changing the character of this respi-
ration we may artificially control their action.
12. That the c/jZorqp%ZZia» respiration does not favour, but that ilie general
respiration does favour the production of alkaloids.
13. That the jiresencc or absence of light has a great influence (through the
respiration) on all the above phenomena.
14. That the laticifcrous ducts dwindle and disajjpear coincidently with the
formation of the alkaloids.
15. Tliat the liber fibres are not the place of deposit of the alkaloids.
Mr. Howard remarks that the re-establishraent of the bark under
this treatment of mossing h perfect. " I compared this at first " (he
says)—as indeed the first specimens sent seemed to justify— "to the
granulation of flesh over the surface of wounds; hut the accompanying
drawings, under the microscope, show the bark in the third time of
renewal to be perfectly renewed, as is the case in the parts replaced
by animals of low organization, as the claw, for instance, is formed
again after being lost by the lobster."