ble of the poor man and his
lamb; 2 Sam. xii. 1. or like the parables in the New Testament; as
otherwise knowledge could not be said to grow upon one tree, and life
upon another, or a serpent to converse; and lastly that this account
originated with the magi or philosophers of Egypt, with whom Moses was
educated, and that this part of the history, where Eve is said to have
been made from a rib of Adam might have been an hieroglyphic design of
the Egyptian philosophers, showing their opinion that Mankind was
originally of both sexes united, and was afterwards divided into males
and females: an opinion in later times held by Plato, and I believe by
Aristotle, and which must have arisen from profound inquiries into the
original state of animal existence.

ADDITIONAL NOTES. XI.

HEREDITARY DISEASES.

The feeble births acquired diseases chase,
Till Death extinguish the degenerate race.
CANTO II. l. 165.

As all the families both of plants and animals appear in a state of
perpetual improvement or degeneracy, it becomes a subject of
importance to detect the causes of these mutations.

The insects, which are not propagated by sexual intercourse, are so
few or so small, that no observations have been made on their
diseases; but hereditary diseases are believed more to affect the
offspring of solitary than of sexual generation in respect to
vegetables; as those fruit trees, which have for more than a century
been propagated only by ingrafting, and not from seeds, have been
observed by Mr. Knight to be at this time so liable to canker, as not
to be worth cultivation. From the same cause I suspect the degeneracy
of some potatoes and of some strawberries to have arisen; where the
curled leaf has appeared in the former, and barren flowers in the
latter.

This may arise from the progeny by solitary reproduction so much more
exactly resembling the parent, as is well seen in grafted trees
compared with seedling ones; the fruit of the former always resembling
that of the parent tree, but not so of the latter. The grafted scion
also accords with the branch of the tree from whence it was taken, in
the time of its bearing fruit; for if a scion be taken from a bearing
branch of a pear or apple tree, I believe, it will produce fruit even
the next year, or that succeeding; that is, in the same time that it
would have produced fruit, if it had continued growing on the parent
tree; but