76
ABSTRACTS
white descendants. One who did not know the cross-bred origin of these mice may put
this down as due to the influence of the first father. But the same result would have
been realised even if the latter mating had taken place first. It is unavoidable. To
utilise telegony in order to explain this is, therefore, radically wrong.
The author explains that the cases he quoted earlier as examples of those advanced
in favour of telegony are again nothing but instances of operation of the ordinary
Mendelian law of heredity.
With reference to the case of two white swine giving birth to pigmented piglings, the
explanation lies in the fact that matings between swine and wild boar are not rare, and
that a wild boar should have been used in the past in building up this race of swine. A
recent experience of L'ecole d'Alfort is illustrative. Some years ago matings were made
between the wild boar and the Large-White swine of the school. Through selection, and
elimination of the tainted, a strain was built having all the appearance of a pure race of
Large-White. Two of these perfectly white subjects have now given birth to a piglet
with wild boar characteristics.
With reference to the black Angus bovines without horns giving rise to a roan subject
with horns, the author advances a similar explanation. The two Angus parents should
have had a horned roan coloured ancestor in the distant past. One knows that the
absence of horns and black colour dominate over the presence of horns and roan coloration.
It is, therefore, possible that the latter characters have remained latent in some animals as
recessive factors. When two such animals accidentally come together, certain of their
offsprings get these factors in the duplex condition with the result that the recessive
factors become exteriorised.
The author explains the case of two furless dogs giving rise to a furred one, as only
an expression of the existence of a dominant " lethal character ". Hairless skin in the
dog is a lethal character, that is to say, young ones that could have this character in the
duplex condition and be genotypically hairless are never born, but suffer death in their
embryonic life. The hairless dogs are therefore all cross-breds, and will never breed
true but always throw a proportion of furred offspring. This happens invariably without
exception. The lethal character is a proven factor in genetics, and the case in question
seasily explained thus without having to invoke telegony.
It is therefore concluded that telegony is a myth. [V. R. R.]
Report of the Special Committee appointed by the National Veterinary Medical
Association to study the subject of Small Animal Euthanasia, 1938. (Published
by the National Veterinary Medical Association of Great Britain and Ireland,
London. Price 5s., 1937.)
AT the instance of the National Veterinary Medical Association of Great Britain
and Ireland, a special Committee was appointed to study and express opinion on the
existing methods of painless destruction of small animals. '' The remit to the Committee
was in the following terms :—
" (a) That the Committee be requested to explore in all its bearings the subject of
small-animal euthanasia, i.e. of dogs, cats and birds with a view to arriving
at an authoritative opinion as to which is the most efficacious method of
humanely destroying these animals.