1. Human monstrosities are of great interest to the
physician, surgeon, and obstretician.
|| 2. Until the 19th century, malformations were attributed to the influences of wrathful gods, devils,
witches, sex perversions, the moon, eclipses,
comets, and "maternal impressions".
|| 3. Scientific teratology only commenced in the
17th century.
|| 4. Connections between animals of different species
have been proved conclusively to be sterile.
|| 5. Germinal life of embryo lasts about one week.
|| 6. Embryonic life lasts about five weeks.
|| 7. Foetal life lasts for the remainder of the
ante-natal period.
|| 8. Normal development is a form of twinning -
"symmetrical division".
|| 9. Uniovular twins originate from one ovum, and is
not a normal physiological process.
|| 10. Double monsters also originate from one ovum,
and are due to partial fission of embryonic axis.
|| 11. Binovular twinning is not true twinning.
|| 12. The armadillo has supplied valuable data regarding
early mammalian development.
|| 13. The corpus luteum is a guide as to the number
of ova involved in a pregnancy.
|| 14. There is a period of quiescence of about three
weeks in early development of the armadillo.
This may explain its polyembryony, and may
also explain uniovular twinning in man.
|| 15. Twinning is due to a period of quiescence as
a result of an upset in the growth regulating
mechanism of the ovum.
|| 16. In epignathus we have complete fission with
partial inclusion
|| 17. In foetus in foetu we have complete fission
with total inclusion.
|| 18. Malformations can be produced experimentally
in some animals by:
(1) violent agitation,
(2) variations in physiochemical conditions,
(3) variations in temperature, and
(4) disturbance of normal respiratory interchange.
|| 19. The principal causes of human malformations are:
(1 )amniotic bands or adhesions,
(2) faulty implantation of ovum due to endometritis,
(3) developmental arrest at critical stases
of gastrulation, and
(4) heredity.
|| 20. There is a growth regulating mechanism in the ovum.
|| 21. This mechanism is controlled by two ovular secretions:
"inhibitin" which inhibits growth, and
"stimulin" which stimulates growth.
|| 22. Normal tissues contain a similar mechanism with
similar secretions.
|| 23. In ante-natal life, inco-ordination between
these two factors leads to mal- developments
and. monsters,
|| 24. In post -natal life such into -ordination results
in simple or malignant growths.
|| 25. "Inhibitin" may prove a powerful "de- cancerising" agent
|| 26. "Stimulin" may prove equally useful in most
clinical conditions of a non -malignant nature
requiring the speeding-up of tissue repair.
|| 27. Surgery has a distinct field of usefulness in
certain cases of double monsters namely,
omphalopagus parasiticus, xiphopagus, thoracopagus
and craniopagus.
|| 28. Heredity is a potent factor in physical and mental
peculiarities in the offspring.
|| 29. There is a constant tendency towards recovery
and return to a healthy stock.
|| 30. Eugenics is " the study of the agencies under social control that may improve or impair the racial qualities of future generations, either physically or mentally".
|| 31. Mendel's laws of heredity have been found also applicable in man as regards mental and physical characters.
|| 32. Several methods for checking the supply of human defectives have been proposed e.g. segregation, sterilisation, restrictive marriage, laws, etc.
|| 33. Eugenics is one of the world's most pressing problems
