For further information on this subject, the reader is referred to the Tentamen Medicum of Dr. Jeffray, printed at Edinburgh in 1786.  And it is hoped that Dr. French will some time give his theses on this subject to the public.

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SECT.  XXXIX.

OF GENERATION.

  Felix, qui causas alta caligine mersas
  Pandit, et evolvit tenuissima vincula rerum.

I. Habits of acting and feeling of individuals attend the soul into a future life, and attend the new embryon at the time of its production.  The new speck of entity absorbs nutriment, and receives oxygene.  Spreads the terminations of its vessels on cells, which communicate with the arteries of the uterus; sometimes with those of the peritoneum.  Afterwards it swallows the liquor amnii, which it produces by its irritation from the uterus, or peritoneum.  Like insects in the heads of calves and sheep.  Why the white of egg is of two consistencies.  Why nothing is found in quadrupeds similar to the yolk, nor in most vegetable seeds. II. 1. Eggs of frogs and fish impregnated out of their bodies.  Eggs of fowls which are not fecundated, contain only the nutriment for the embryon.  The embryon is produced by the male, and the nutriment by the female.  Animalcula in semine.  Profusion of nature’s births. 2. Vegetables viviparous.  Buds and bulbs have each a father but no mother.  Vessels of the leaf and bud inosculate.  The paternal offspring exactly resembles the parent. 3. Insects impregnated for six generations.  Polypus branches like buds.  Creeping roots.  Viviparous flowers.  Taenia, volvox.  Eve from Adam’s rib.  Semen not a stimulus to the egg. III. 1. Embryons not originally created within other embryons.  Organized matter is not so minute. 2. All the parts of the embryon are not formed in the male parent.  Crabs produce their legs, worms produce their heads and tails.  In wens, cancers, and inflammations, new vessels are formed.  Mules partake of the forms of both parents.  Hair and nails grow by elongation, not by distention. 3. Organic particles of Buffon. IV. 1. Rudiment of the embryon a simple living filament, becomes a living ring, and then a living tube. 2. It acquires irritabilities, and sensibilities with new organizations, as in wounded snails, polypi, moths, gnats, tadpoles.  Hence new parts are acquired by addition not by distention. 3. All parts of the body grow if not confined. 4. Fetuses deficient at their extremities, or have a duplicature of parts.  Monstrous births.  Double parts of vegetables. 5. Mules cannot be formed by distention of the seminal ens. 6. Families of animals from a mixture of their orders.  Mules imperfect. 7. Animal appetency like chemical affinity.  Vis fabricatrix and medicatrix of nature. 8. The changes of animals before and after nativity.  Similarity of their structure.  Changes in them from