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ALBERT R. MANN
LIBRARY
AT
CORNELL UNIVERSITY

The Penycuik experiments,

Cornell University

Library

The original of this book is in
the Cornell University Library.

There are no known copyright restrictions in
the United States on the use of the text.

http://www. archive.org/details/cu31924001033855

THE PENYCUIK EXPERIMENTS.

By the same Author.

A CRITICAL PERIOD IN THE DEVELOPMENT
OF THE HORSE.

Price ONE SHILLING NET.

“Tndeed it is almost idle to attempt to deal with Professor Ewart’s
work at all, when one is so entirely behind him in regard to scientific
knowledge. Still there remains this fact, that what he explains
practical breeders and their stud-grooms have never been blind to.
... I am quite sure from the benefit I myself have derived from
the’ perusal of his work, that there is not a breeder in the kingdom
who would not be the better for possessing it.’—Sportsman, Jan 15th,
1898.

A. & C. BLACK, SOHO SQUARE, LONDON.

In the Press.

ZEBRAS AND ZEBRA HYBRIDS.

THE

PENYCUIK EXPERIMENTS.

BY

J. C. EWART, M.D., F.BS.,

REGIUS PROFESSOR OF NATURAL HISTORY, UNIVERSITY OF EDINBURGH.

WITH ILLUSTRATIONS.

LONDON
ADAM AND CHARLES BLACK
1899

All rights reserved.

CONTENTS.

GENERAL INTRODUCTION

(1) Zebra Hybrids. (2) The Principles of Breeding—
(a) Reversion in Pigeons, Fowls, Dogs, Rabbits,
Ducks, and Horses; (6) Prepotency and In-
breeding. (3) Telegony. (4) Saturation. (5)
Sterility in Equine Hybrids.

PART I.

A. The Birth of a Hybrid between a Burchell’s Zebra
anda Mare .

(This paper is reprinted with a few verbal
alterations from The Veterinarian for November,
1896.)

B. Zebra-horse Hybrids

(This paper is reprinted from The Zoologist for
February, 1898.)

PART II.
Telegony and Reversion

(This paper in an abridged form was published
in The Veterinarian, November and December,
1897, and February, 1898.)

APPENDIX.
Telegony

(Reprinted from The Veterinarian, April and
May, 1895.)

PAGE

165

SON AKe ws

LIST OF ILLUSTRATIONS.

. Matopo, a Burchell zebra .
. Mulatto, a West Highland pony

rf and her hybrid Romulus seven days old
Romulus, twenty-seven days old
” ” face view

. Matopo, left side

”

“i eh side

. Mulatto, and Romulus seven fie. old
. Romulus, view of face

i one year old

2. Brenda, a Clydesdale mare’s hybad
. Lord Morton’s Quagga

” 7 hybrid

. Filly out of Lord Morton’s mare .
. Mulatto
. Matopo, left side

a right side .
r face markings

. Romulus, face markings
. A Somali zebra
. Skin of a Somali zebra, hom a pitatogmen ofa oh ent

by Mr. Charles V. A. Peel, Oxford

. Diagram of stripes of Matopo

- a Somali zebra

JA slnartly with ‘‘ shadow” stripes, from a pholoenh

by Mr. Brown, Penycuik

. A mountain zebra

27. A true Burchell zebra

. Skin of a mountain zebra .

»» 93 Orawshay’s zebra

. Mountain zebra and foal
. Mulatto, and Romulus seven days old
. Romulus twenty-seven days old

3 3 3 face view

4. Somali zebra, face markings

x1
bo

aI.
wo co

vill LIST OF ILLUSTRATIONS.

Fig PAGE
35. Crawshay’s zebra, face markings . : 93
36. Face markings in a Norwegian pony : ; 103
37. A zebra 2, horse 4, hybrid ; . : 119
38. Skin of dam of hybrid shown in Fig. 37. ‘ 120
39. Sire of hybrid shown in Fig. 37. é : : 121
40. Mulatto : ; 141
41. A grey Arab horse (Benne : ‘ 146
42. An ordinary mule—ass 3, horse eo ayheal 148
43. Mulatto’s second foal, from a drawing by Mr. Ragin

Alexander . ‘ : : : : 150
44. Mulatto’s second foal : ; : 151
45. Ridges formed by hair in region of flank feather in a

foal . . , : 155
46. Part of skin oer in Fig. 45 ; 156

Figs. 1, 4, 5, and 42, from photographs by Mr. Charles Reid.
Wishaw.

Figs. 3, 6, 11, 12, and 41, from photographs by Mr. Swan Watson,
Edinburgh.

Figs. 2 and 44, from photographs by Mr. Adderley, Penycuik.

Figs. 19, 20, 23, 24, 36, 45, and 46, from drawings by Mr. Fiddes
Watt.

Figs. 18, 14, and 15.—15 by Mv. Fiddes Watt; 14 and 15 by Mr. R.
KE. Holding, after Agasse’s pictures in Roy. Coll. of Surg. Mus.
London.

Figs. 21, 26, 27, 54, and 35, from drawings by Mr. J. Smit, in
Prazak’s ‘ Wild Horses of Africa,’ MS.

Figs. 28, 29, 37, 38, and 39, from photographs by Mr. Fall, Baker
Street, London.

Fig. 30, from a photograph kindly sent by the Director of the
Zoological Gardens, Amsterdam. The foal is now in the Zoolo-
gical Gardens, London.

For the use of the skins represented in Figs 28 and 29 I am in.
debted to Mr. Rowland Ward, Piccadilly, London.

GENERAL INTRODUCTION.

I Have been frequently asked when an account is likely
to be published of the telegony and other experiments I
started some time ago at Penycuik.* As the problems
under consideration are not of a kind that can be settled
off-hand, and as one inquiry has begotten others, some
years must elapse before a complete and systematic
account is possible.

For the information of those good enough to interest
themselves in some of the problems I have set myself
to solve, I have decided to issue in book form three
papers which have already been published. These papers,
with the help of this introduction (which must also serve
as a preface, and to a certain extent as a supplement),
will indicate the lines along which the inquiries are pro-
ceeding, and also the kind of answers likely eventually
to be made to some of the questions.

The first two papers deal with five of the zebra
hybrids I have bred; the third—which has grown out of
an address prepared nearly a year ago—deals chiefly with
reversion and telegony.

The three papers having been written at different
times and for different objects, a certain amount of re-
petition has been inevitable. ‘This will, I think, prove
advantageous rather than otherwise ; it will at least help
in fixing in the mind of the reader the difference in
the arrangement of the stripes in the Burchell zebra
stallion ‘“‘ Matopo” from that in his hybrid offspring.

* Penycuik is pronounced (as it was often formerly spelt.) Pennycook.
It means the hill of the cuckoo. Now the usual spelling is Penicuik, but
until comparatively recently, as in olden times, a “‘y”’ was almost in-

variably used. Whether the Post Office or the North British Railway
Company. deserves most blame for the change it is hard to tell.

b

x GENERAL INTRODUCTION.

When I came to seriously consider the “ infection 22 Or
telegony problem, it was at once evident that a special
study of the bands, stripes, and other markings in the
Equide was indispensable. Though much has been
written bearing on the coloration of zebras, I failed to
find anything approaching a full account of the plan of
the stripes in even the mountain zebra (Hquus zebra),
which has been almost constantly under observation in
England for more than a century. Hence the necessity
of working up, as far as the available material permitted,
the whole coloration question in the Equide, and hence
it is that so much space is occupied with a description of
the bands and stripes in my zebra stallion, and with
pointing out how he differs from other zebras and from
zebra hybrids.

It will be gathered from the first paper that I started
with the idea that there are three kinds of zebras, each
having its own distinctive characters. I still believe that
there are three distinct types of zebras, but I no longer
believe that all three types can be readily distinguished
from each other by their markings. The three types are
(1) Grevy’s zebra (H. grevyt) of Shoa* and Somaliland ;
(2) the mountain zebra (B. zebra), once common in South
Africa, and generally referred to in old works as “ the
zebra,” or “the common zebra ;”’ and (3) the widely dis-
tributed Burchell group of zebras, including many species—
or, at least, sub-species and varieties,—some of which are
unfortunately often spoken of as quaggas. At the risk
of iteration I may add that the Somali or Grevy’s zebra
(for a time confounded with the mountain zebra of South
Africa) stands apart from all the others. It is profusely
striped, measures sometimes quite fifteen hands (sixty
inches), and is, I think, the most primitive of all the
living striped horses. I considered the mountain zebra
equally distinctive until some months ago, when I came
across a skin which seems to connect this long-known

* It was doubtless the Shoa zebra, and not, as has hitherto been taken

for granted, the mountain zebra of South Africa, that was exhibited in the
Roman amphitheatre during the third century of the present era.

GENERAL INTRODUCTION. “Xi

Species with certain less familiar members of the great
Burchell group found in Nyassaland. There is hence no
link now wanting in the chain (if the striping alone is
considered) that has at one end the common mountain
zebra, with a “ gridiron ” over the hind quarters, and legs
barred to the hoofs, and the true Burchell zebra, with
perfectly white legs and scarcely a vestige of transverse
stripes across either croup or loins. From the true Burchell
zebra it is but a step to the better marked specimens of
the now lost if not extinct quagga (HE. quagga). How
the members of the Burchelli group will be eventually
arranged does not concern us, as we are fortunately no
longer expected to believe in the fixity of species.

Quite as much attention might have been directed to
the form, &c., of the hair as to the arrangement of the
stripes in the Equide. But an exhaustive study of the
form, colour, and length of the hair of the Equide and
their hybrids at different seasons and in different areas
would occupy a lifetime.*

ZEBRA HYBRIDS.

I have bred nine zebra hybrids by crossing mares of
various sizes (from 11 to 15 hands) and breeds with my
zebra stallion ‘ Matopo,”? and I have in my possession
three hybrids out of zebra mares, one having for his
sire a donkey, the other two were sired by ponies. The
hybrids are to me especially interesting. because of the
curious blending of characters, derived apparently partly
from their actual and partly from their remote ancestors,
and because they shed new light on many questions of
general interest, such as the origin of stripes, reversion,

* As it happens, Nathusius has already done admirable work in this
field, and I trust he may yet increase our obligations by new observations
and discoveries. Nathusius finds that in its hair the Somali zebra stands
apart from all the rest, and that in zebra hybrids the hair neither
resembles that of their parents, nor yet does it occupy an intermediate
position.

xi GENERAL INTRODUCTION.

interbreeding, and prepotency. The reversion hypothesis
or dogma is an extremely fascinating one. It has long
interested breeders of all kinds, yet it is still shrouded
in mystery. It is commonly believed that a child some-
times, instead of taking after its father, closely resembles
its father’s mother, or is the image of its own mother ;
but we are still a long way from accounting for such
phenomena. As is pointed out in the second paper,
some of the hybrids in make and disposition strongly
suggest their zebra sire, others their respective dams ;
but even the most zebra-like in form are utterly unlike
their sire in their markings. It is not a matter of taking
after a grandparent, but after an ancestor in all proba-
bility thousands of generations removed, an ancestor
probably far more like the Somali than any of the Bur-
chell zebras.

Closely connected with reversion is the question of
prepotency. It is generally assumed that an old species
or variety is prepotent over a more recent species or
variety. It 1s impossible to say whether zebra hybrids
in their markings take after a remote zebra ancestor, or
after an ancestor common to both zebras and horses, or
after a hypothetical mid-parent combining the characters
of the less remote ancestors of both zebras and horses.
There is, however, no difficulty in seeing that while some
zebra hybrids, apart from their stripes, closely resemble
the zebra parent, others take after their horse parent,
thus showing that the wild sire is not necessarily the
most prepotent. But even when the hybrids are dis-
tinctly horse-like they never repeat recently acquired
peculiarities, such as a blaze or short ears, high withers,
or a small head and long neck.

It would not, e.g., judging from the results already
obtained, be possible to breed from a piebald mare a
hybrid showing patches of white; even from a mare
that produced a piebald foal to a whole-coloured horse,
This, I think, is not because of the prepotency of the
wild sire, but because there is reversion at least in
the body colour towards the wild and never gaudily

GENERAL INTRODUCTION. Xi

coloured ancestors of the horse, as well as to the
primitively decorated ancestors of the zebra.

In addition to throwing light on reversion and pre-
potency, the hybrids are interesting in being, in some
respects, almost intermediate between their parents. In
Romulus the mane is nearly intermediate ; in Remus it is
always upright ; while in two others it is long and almost
horse-like in winter, but short and upright in summer.
Again, the warts (chestnuts) are sometimes intermediate.
In some they are quite absent, as in zebras, from the hind
legs ; in others they are present, but less than half the
usual size, or there is only one present, less than a third
the usual size. The warts on the fore-legs may be large,
oval, and smooth, as in the zebra sire; or smaller,
rounded in form, and half as prominent as in the horse.
In the same way the hoofs vary, being almost interme-
diate in some, zebra-like in others.

Romulus, the oldest of my hybrids, measured at the
withers on his second birthday nearly as much as his
sire. In many respects he resembles his dam (Mulatto),
the black Highland pony ; in some respects he is a zebra.
In the head and neck he is less like Mulatto than or-
dinary Highland ponies, as if he took after some of
Mulatto’s less refined Highland ancestors. From the
shoulders backwards the hybrid is getting more and more
like his dam, and less like his zebra sire, in which the
sides are flattened, while the muscles of the back stand
out at each side of a median spinal groove. Mounted
on perfect legs, Romulus moves freely and rapidly, and
often carries himself as proudly as a zebra. He has
already been in harness, and, being very docile, he onght
when older to prove as useful as he is attractive.

While in make the horse predominates in Romulus, he
takes after the zebra in his constitution and habits. A
zebra is in all respects more intense than a horse, he is
more on the alert, more timid and suspicious, and yet more
imbued with curiosity. When he once decides to take
action he moves more rapidly than a horse, is more regard-
less of consequences, and usually suffers less from an in-

X1V GENERAL INTRODUCTION.

jury than from the shock to his nervous system. One
evening, when Matopo had refused for hours to retire
into his box, I threw a rug over him. He bounded across
the court (first nearly upsetting a mare, and then nearly
breaking his neck against the fence), and then rushed
around his box until the dreaded object was got rid of.
Had it been a lion the panic could hardly have been
greater, but he soon learned that a rug, however sug-
gestive, was perfectly harmless. Strangely enough, when
a zebra-skin is hung up within sight of Matopo he be-
comes excited. He arches his neck as if preparing for
single combat, and, though he refuses to approach the
skin, he is evidently not consumed with fear, as is the
case when a coil of rope is carried up to him. It has
been suggested that the rope appeals to his instinctive
dread of serpents, but I consider this unlikely. A
serpent-like object he strikes at with his hoofs; when his
legs are touched with a rope he drops on his knees or lies
down altogether.

The other day Matopo escaped from his paddock, and
eventually found his way down three grass steps on to a
lawn. On two sides the lawn is bounded by a fairly steep
shrub-clad bank, on the other two it slopes somewhat
rapidly to a footpath. Nothing would induce Matopo to
descend this slope. He galloped gaily round the lawn as
if he were in a circus, and was with difficulty persuaded
to return the way he came. A somewhat timid Exmoor
pony went up and down the slope, on to and off the lawn,
without any hesitation. Probably the zebra, had he been
left to himself long enough, would have made a complete
inspection of the garden.

The behaviour of the zebra interested me, because his
hybrid son Romulus had previously conducted himself in
a similar fashion when taken on to the Jawn to be photo-
graphed. Romulus eventually, tempted by corn, allowed
himself to be led away from the lawn along a narrow grass
border from which return, without leaving the grass, was
impossible, Though Romulus in many ways behaves like
his sire, he is, compared with most zebras, “as water unto

GENERAL INTRODUCTION, xV

* +9
wine ;*’ and, though it may take longer to break zebra

hy bride tin loesen: they will, I believe, be more amen-
able than ordinary mules, and, if one may judge from a
single case, infinitely more easily managed than zebra-ass
hybrids. I may here mention that the figures illustrating
the papers give a very imperfect idea of Romulus and the
other hybrids. They are generally considered more at-
tractive than their respective dams, and handsomer than
their gaily painted wild sire.

Remus, the bay Irish mare’s hybrid, is, PicHeN only a
yearling, already taller than Romulus. Notwithstanding
the longish head and upright mane, he is in many ways
very like his dam. The body colour is bay ; the stripes,
which are abundant and pronounced, and, except on the
forehead, arranged as in Romulus, are of a dark brown
colour, Before completing his first year he had formed
for himself a small herd of fillies, which he guards
jealously from all intruders. As a foal his curiosity was
so great that if I knelt down and looked at a particular
tuft of grass he came up, and with lowered head gazed
steadfastly in the same direction.

Brenda, though out of a larger mare, is smaller than
Remus, more heavily built, and much lighter in colour.
With the exception of her unusually long mule-like ears
and low withers, she is more a horse than a zebra, in
gait and disposition as well as in form. MHeckla, the
offspring of a yellow and white Iceland pony, has from
the first been dark in colour, and but faintly striped on
the neck and over the hind quarters. Apart from her
stripes, mule-like ears and tail, she is not unlike a pony.
Strangely enough she steps high like a hackney, though
her dam almost invariably moves like a pacer. Norette,
the offspring of a small black Shetland pony, is extremely
zebra-like throughout. In the form of the head, neck,
and hind quarters she is remarkably like a typical
Burchell’s zebra I saw recently, and she sometimes
reminds me forcibly of some of the photographs of the
lost quagga. During the winter Norette’s mane was
long and hanging to both sides, as well as freely over her

Xvi GENERAL INTRODUCTION.

brow, but during the summer it has been as short as in her
zebra sire. Like her dam she had a very thick winter
coat, consisting of long hairs; but her summer coat is
smooth and shining, and made up of quite short hairs.
Though very like a zebra in make, this hybrid moves in
a somewhat different fashion from her sire. This may
be partly owing to her hoofs being unusually long,—they
are relatively longer and more pointed than in Matopo.

During the present summer four new hybrids by
Matopo made their appearance. Brenda’s dam produced
a second hybrid which has led to no little speculation.
Brenda, but faintly striped, might, at a little distance,
were it not for her long ears and low withers, be
taken for a half-bred yearling colt. The new hybrid
(Brenda’s own sister) is very dark in colour and quite a
zebra in actionand habits. Last year some accounted for
Brenda showing little of the zebra by saying her dam, the
small cross-bred Clydesdale, was inbred, and they now
account for her full sister (Black Agnes) being zebra-like
by saying their common dam has been “ infected,”’ or, to
use Bruce Lowe’s term, “saturated,” by their common
sire Matopo. Should the Clydesdale mare have a third
hybrid, and then an ordinary foal, something definite may
eventually be established, both as to “saturation”? and
telegony.

But Black Agnes is interesting for yet another
reason. In Mulatto’s second foal, as is fully described
in the telegony paper, there were several stripes across
the croup, at nearly right angies to the spinal ridge. In
foals of mares that have neither had offspring to zebras nor
asses, markings are at times seen across the hind quarters
—subtle bands, not due, as a rule, to colour, but rather
like water-marks on silk. Again, in one of Lady Meux’s
hybrids out of a zebra mare, and in two dun-coloured
cobs I have had under observation, there are vestiges
of fairly broad stripes across the loins and croup—stripes
more like the bars of the gridiron in the mountain zebra
than the narrow zigzag lines in Romulus and some of my
other hybrids. In Black Agnes there were, at birth,

GENERAL INTRODUCTION. XVii

“water-marks ” and faint stripes over the hind quarters
as well as the characteristic hybrid stripes and rows of
spots. We had, as it were, a double photograph showing
faintly the markings which seem to belong to the ancestors
of the true horses, overlying stripes and spots presumably
inherited from the ancestors of the zebras. In other
words, in the markings of Black Agnes we seem to have
a reversion towards the ancestors of the dam as well as
the sire.* Whether any vestiges of the double printing
will be visible next spring it is impossible to say.

An unexpected event this summer was the birth of
twin hybrids—a colt and filly. Unfortunately one of
the twins, the filly, though well developed and perfect in
every way, died almost as soon as it was born. The dam
of the twins is a 14:2 hands thoroughbred, light chest-
nut mare, with high withers and a prominent breast-bone.
The surviving twin, though striped like Romulus, re-
sembles his dam in the body colour, but he will probably
become darker as he gets older. He already, though in
many ways lke a zebra, looks quite different from his
half-sister Black Agnes. But, however much they differ
in appearance, they closely resemble each other in their
attitudes and movements. Like a hinny foal (a hybrid
between an ass and a Welsh pony stallion) they step high
when trotting, and if any one is near, the head is carried
nearly on a level with the neck but to one side, apparently
that they may keep an eye on the intruder. At the
gallop the head is carried in the middle line, but as soon
as they break into atrot the head is moved from one side
to another by way of determining the position of the
possible enemy. It has been said the gallop is the
natural pace of the horse. This I very much doubt; it
is certainly not the ordinary pace of a zebra. When
pursued by enemies, and when advancing to attack a
rival, zebras move at the gallop, but under ordinary cir-
cumstances they proceed at a leisurely dignified trot.

* In zubra-ass hybrids the spinal and shoulder stripes and the leg bars

are evidently inherited through the donkey sire, not, as might have been
expected, from the zebra dam,

xvi GENERAL INTRODUCTION.

Some of my hybrids in their movements are not unlike
their sire, but the two foals just referred to remind me
more of a young stag I watched trotting round a paddock
during the present summer. Whether this very elegant
action will be maintained as they increase in size remains
to be seen.

I may here mention the surviving twin has helped to
assure me that hybrids may have as marvellous powers
of recovering from severe injuries as zebras. ‘Two years
ago a zebra mare dragged from its place a heavy iron
feeding-trough. The trough was soon broken, and as
the mare reared and swung the trough about her loose
box, ere the rope could be severed her fore-limbs were
cut and bruised to an alarming extent. In a few days
she was all right again. The wounds healed without
suppurating, and without any swelling of the limbs.
Quite recently Matopo, when turning rapidly on the way
from his paddock, came into violent contact with one of
the rails of an upright fence. The skin between the two
halves of the lower jaw was torn so as to form a deep
pocket large enough to hold a walnut. Stitching was
out of the question, but in a few days the pocket was
closed, and the wound has mended so well that no scar
or irregularity in the striping can be detected.

The twin was found one morning, when about two
months old, with a flap of skin five inches long, and
averaging one and a half inches in width, hanging down
over the front of the left fetlock. The skin was replaced
and stitched* along one side, but the upper part being dead
was cut off some days later. For a time the wound
looked hopeless enough, but now it is quite healed, and
only a very small scaris left. As in the zebra mare, there
has been no lameness, and from first to last a complete
absence of swelling either below the wound at the fetlock
or above in the vicinity of the knee.

One of this summer’s hybrids unfortunately died when

* During the stitching the little hybrid fought desperately, and cried

piteously, sometimes uttering short barking sounds or crying like a
wounded hare.

GENERAL INTRODUCTION, x1x

hardly three months old. The dam in this case was a
young bay, small thoroughbred Irish mare. Mules are
said to be hard to rear, but so far, with the exception
mentioned, there has been no difficulty with my hybrids.
The hybrid that succumbed was very faintly marked, and
in most respects more a horse than a zebra. The dam,
barely three years old when the hybrid was born, suf-
fered from the Strongylus scourge during the winter,
and was consequently out of condition during the spring.
Moreover I believe the dam is a victim of inbreeding.
One of the evils of inbreeding is that the young are
often difficult to rear, succumbing sometimes to one
disease, sometimes to another. This hybrid, though weak
to start with, did extremely well for a time, but after a
few days of unfavorable weather it took ill and died
quite suddenly from what seemed to be an attack of acute
rheumatism. Several other foals, having quite as well
bred dams, living under exactly similar conditions, suffered
not at all.

Before leaving the hybrids, I may say that since
Romulus appeared on the scene Baron de Parana has
succeeded in crossing a Burchell zebra and an ordinary
mare in Brazil. Baron de Parana seems to have satisfied
himself that all attempts to cross a male Burchell zebra
and a mare prior to 1892 (when he began his experi-
ments) bad failed. Notwithstanding this, he set to
work and eventually succeeded, his hybrid arriving not
many months after the birth of Romulus. Though
summer succeeded summer without the expected results,
the Baron, with exemplary patience, continued his
experiments until success crowned his efforts. All who
have had experience in work of this kind will heartily
congratulate Baron de Parana, and wish him still further
success.

xx , GENERAL INTRODUCTION.

THE PRINCIPLES OF BREEDING.

The uncertainties of stock-breeding are proverbial,
and fanciers are seldom surprised when the unexpected
happens. We speak of the principles of breeding and
of scientific breeders, but it looks often as if there were
no principles, and as if in breeding the scientific method
is inapplicable. Why of all vocations should the
breeder’s be the most uncertain? or shall the question
rather be, why of all men should breeders be the most
unreasonable, more than all others desirous to ‘“ eat their
cake and have it”? The fundamental reason doubtless
is that wherever there is life there is variation in one or
more directions. Variation is welcomed by breeders and
fanciers up to a certain point, but beyond this it is
considered a positive disadvantage. When a desired
strain, variety, or breed has been formed the breeder
would like to arrest all further variation. As with a key
an electric current is switched off, he would like to
arrest further change. But not only has variation to be
contended with, there is reversion and the evils that flow
from inbreeding. Hven when making a new strain much
patient work may be lost through prepotency or sterility
unexpectedly supervening where least wanted.

Can science do anything to make the work of the
breeder less uncertain and haphazard? Can it help in
the production of new forms, and stereotype them when
once realised, so that they may be reproduced, “‘ repeated ”’
with as much certainty as statues are turned out of a
mould? Science is incapable of either creating or,
except to a limited extent, controlling life, but yet it may
help the breeder to so influence the vital forces in
operation that the desired goal is reached without un-
necessary waste of time or energy.

To all who give a moment’s thought to the subject it
will be evident that variation, reversion, inbreeding, and
prepotency have to be especially reckoned with. Science,
in as far as it throws light on these subjects, will doubt-

GENERAL INTRODUCTION. XXi

less be useful. On the great and all-important subject
of “ variation” my experiments have no direct bearing,
but they justify my referring shortly to reversion, pre-
potency, and inbreeding.

1. Reversion.—Nearly ten years have elapsed since Mr.
Galton’s work on ‘Natural Inheritance’ appeared, and
yet but few breeders seem to fully realise that the off-
spring often take not so much after their immediate as
after their less remote ancestors, that probably in all
cases there is more or less marked “ regression towards
mediocrity.” If there is any truth in evolution, it is
extremely probable that the protoplasmic units of which
any given individual is composed have to encounter and
overcome during development countless numbers of cor-
responding units representing the component parts of a
long series of lost ancestors. If for any reason units
representing the latest development of the race or variety
—the latest variations, mental or physical—are unable to
assert themselves, are lacking in power or stability,
older and more potent units will take their place, and thus
lead to regression or reversion. The reversion may be
to recent, remote, or intermediate ancestors, and the
tendency will in most cases be to revert to “sports”
that here and there mark the route along which the
development has proceeded.

Any two individuals may be likened to two pictures.
Even if portraits by the same artist of two members of
the same family, they would differ in form as well as in
colour. Were it possible to blend two such pictures into
one, the result would be a picture differing from the
originals, but not necessarily intermediate between them.
Some of the pigments (having been differently made up)
might neutralise each other, and latent colours—colours
which, for some reason or other, had been obscured in
one or both of the originals—might come to the surface.
There would be a loss of the characters which served to
distinguish the individuals from each other and the rest
of their relations, but yet there would doubtless be hints
here and there of the originals, and, because of the blend-

XxX GENERAL INTRODUCTION.

ing, suggestions of some of their ancestors. The offspring
of two individuals (unless very closely related) differ in
much the same way, only the possibilities for variation
are infinitely greater. The raw material, the living clay
or protoplasm, out of which the new individual is de-
veloped, comes, as it were, from different quarries, with in
each case a different history. In the struggle amongst
the parts, as the development proceeds the legionaries of
the immediate ancestors are sometimes worsted by those
of the less recent ancestors, the grandparents being vic-
torious in the centre, while still more remote ancestors
secure occasional successes in the wings. The final result
is in most cases a drawn battle, neither particularly satis-
factory to those immediately concerned, nor to the world
at large.

According to Mr. Galton’s law of ancestral heredity,
the two parents contribute half, the four grandparents
one fourth, the eight great-grandparents one eighth, and
so on, of the total heritage of the average offspring. It
is, however, conceivable that, owing to what, for want
of a better name, may be called antagonism between
the protoplasmic units during fertilisation and develop-
ment, the grandparents, or even the great-grandparents,
might contribute more than the immediate parents, and
that, when the ‘antagonism ”’ is still more pronounced,
the comparatively remote ancestors might become the
main contributors. Darwin was the first to point out
that the offspring of parents belonging to different
species, or distinct varieties, do not, as might have been
expected, occupy an intermediate position, but take after
aremote ancestor. Now-a-days the possibility of rever-
sion is sometimes called in question. I have never-
theless endeavoured to account for my hybrids differing
in their markings from their sire by the reversion hypo-
thesis, and I have made a number of experiments with
the object of testing the probability of this explanation,
Some of these experiments I shall now mention.

(1) Pigeons.—With the numerous varieties of pigeons a
countless number of experiments have been made by

c

GENERAL INTRODUCTION. XXH.

Darwin, Tegetmeier, and other naturalists, and by a host
of fanciers, These experiments are especially interesting
to biologists, because they point to the conclusion that
the crossing of extreme forms leads to reversion towards
a remote ancestor—in this case to the wild rock-pigeon,
Columba livia. But in addition to this a number of
other deductions have been made. It has been inferred,
é.g., that it is extremely difficult to eradicate blue when it
appears in any strain, and that some breeds are more pre-
potent than others.

As I shall have to refer frequently to the wild roci-
pigeon, I may here quote Darwin’s short but very ac-
curate description of its coloration. He says, “The
wild rock-pigeon is of a slaty-blue colour ; the wings are
crossed by two bars ; the croup varies in colour, being
generally white in the pigeon of Europe, and blue in that
of India; the tail has a black bar close to the end, and
the outer webs of the outer tail feathers are edged with
white except near the tips.’’*

Darwin found that when different varieties were
crossed, the offspring often in the colour of the wings
and tail or in some other respects resembled the blue
rock, and in one instance by crossing a barb-fantail
with a barb-spot g he produced a bird ‘ which was
hardly distinguishable from the wild Shetland species.”
It only appeared to differ in having the head tinted with
red, and like the stomach of a paler blue colour.t

Weismann, in referring to this experiment, says,
“These breeds [the barb, fantail, and spot], as is well
known, differ from the wild pigeon in colour as in many
other details, such as the length of the beak and number
of tail feathers; and it would therefore be interesting
to ascertain whether these racial characters had all dis-
appeared in the grandchild, and had been transformed
into the corresponding characters of the wild species.
Were this so the reversion might be considered complete.
. . . Unfortunately Darwin leaves this point untouched,

* © Animals and Plants,’ vol, i, p. 204,
J Ibid., vol. i, p. 210.

XX1V GENERAL INTRODUCTION.

as he devoted his attention chiefly to the coloration of
the species. It seems to me to be very probable, how-
ever, from several of his statements, that this was also
essentially a mere case of reversion as regards the colora-
tion of the plumage. . . . The other racial characteristics
do not at any rate exclude the possibility of a blue colora-
tion; and thus, on the other hand, reversion to the
blue colour is not necessarily accompanied by a reversion
to all the other characters of the ancestral form.”* I
think, though Darwin does not definitely make the asser-
tion, almost complete reversion in his barb-fantail-spot
cross is implied. Had this cross in its beak or legs, or
length of wings, differed decidedly from the wild rock
standard, the fact would most probably have been men-
tioned.

Whatever uncertainty remains as to the extent of re-
version in pigeons should, however, be dispelled. It is
partly with this object in view, and partly to throw new
light on inbreeding and prepotency, that I have recently
been experimenting with pigeons. Darwin, when dis-
cussing prepotency in the pigeon group, says, “ In making
reciprocal crosses between pouters and fantail pigeons
[7. e. crossing them both ways] the pouter race seemed to
be prepotent through both sexes over the fantail. But
this is probably due to weak power in the fantail, rather
than unusually strong power in the pouter; for I have
observed that barbs also preponderate over fantails.’”+
But not only are some varieties said to be more prepotent
than others, it is generally assumed that certain colours
and markings are latent, and ever ready when there is
any disturbance of the balance to reassert themselves,
To use Mr. Wicking’s words, ‘‘ when a blue or a black
and chequered bird, having black wing bars, once appears
in any race and is allowed to breed, these characters are
so strongly transmitted that it is extremely difficult to
eradicate them.” ¢

“* ©Germ-plasm,’ pp. 323, 324.
+ ‘ Animals and Plants,’ vol. ii, p. 41.
+ Tbid., vol. i, p. 210.

GENERAL INTRODUCTION. xXXV

It thus appears that, in addition to settling whether
there is complete or almost complete reversion in form as
well as in colour, there is the question as to whether the
blue colour and the characteristic bars can be easily eradi-
cated ; and the further question, can the prepotency of
any given breed be increased? can a fantail, e.g., be
made prepotent over a pouter ?*

Let me deal first with the coloration question, Can
the blue colour be altered, and the dark wing bars be
eradicated ? Fanciers, as stated above, seem to agree
that while in certain breeds wing bars may not appear for
many generations if pure-bred birds are used, they almost
invariably come to the surface when intercrossing is re-
sorted to; and they also believe that when once estab-
blished it is a difficult matter getting rid of them.

As it happens, I soon succeeded in getting birds
without wing bars by making crosses, which could hardly
a priort have been expected to give positive results. I
crossed a well-bred dark blue fantail, having all the charac-
teristic bars of a rock-pigeou, with a less well bred fan-
tail, also blue, with the exception of the croup, head, and
tail, in which there were a number of white feathers.

On two separate occasions these blue fantails produced
a well-formed absolutely white fantail. I believe this is
an instance of partial reversion, the explanation being
that the white offspring took after a white parent of their
sire. Fantails are an old breed, and white fantails are
especially common. However unlikely the result may
to some appear, I was quite prepared for it from what I
had already learned about reversion and inbreeding. I
next crossed a white fantail cock (which I believed to be
inbred) with a blue pouter hen. According to the
prevalent view the offspring should have taken after the
blue pouter at least in colour and markings, but as it
happens the cross-bred bird—there was but one—is

* T need not say that in experiments of this kind the desired results, if
they come atall, seldom come at once. Even in the most expert hands
there is a large percentage of failure, but happily from failures something
can generally be learned.

c

XXV1 GENERAL INTRODUCTION,

almost as white as the fantail, while in form it closely
resembles the blue pouter. I see no evidence of reversion
in this instance, nor yet of prepotency of the male over
the female. It is a case of each parent handing on its
most fixed individual characters, the fantail giving the
colour, the pouter the form and disposition. The white
fantail cock, which in colour proved prepotent over the
blue pouter, was next mated with a cross between an
owl and an archangel. The archangel hen was a very
good example of the copper-coloured variety, the sides
of the wings and tail being of a bronzed black hue, and
the peak or crest well developed. The owl belonged to
the powdered blue English variety. It is small and
compact, with a very short ‘owl-like” beak, rounded
head, prominent frill, and short legs.

The owl-archangel cross is far more an owl than an
archangel. There is, in fact, nothing either in the colour
or form to suggest the archangel parent, and though
evidently related to an owl it differs in having the head
and beak elongated, in the length of the lees, the
absence of a frill, and also in having the wing bars less
distinct, and the wing coverts chequered with brown.
In all its movements it is nearer the blue rock than an
owl, and, as in the blue rock, there is a white croup and
twelve tail feathers, the outer one at each side edged
with white except near the tip. The head, tail, and
croup approach the European blue rock in colour, but the
breast and wings are tinged with brown.

The fantail with which the owl-archangel hen was
mated is absolutely white, has thirty feathers in its tail,
and is sufficiently prepotent to produce an almost white
bird with a blue pouter. When the feathers eventually
appeared on the offspring of the white fantail and the
owl-archangel I was not a little surprised to find that
both young birds were blue, one of them almost identical
with a young wild blue rock-pigeon.

The wild blue rock varies considerably in colour. In
Shetland, where little, if any, intercrossing with the
dovecote pigeon has taken place, the croup is as a rule

GENERAL INTRODUCTION. " xxvil

white, and the wings in front of the bars of a uniform
light blue colour. In India the croup is generally blue,
while the wing coverts are chequered with black. In
Madeira, through abundant chequering the front part of
the wings often looks almost black. In one of my young
birds the croup and wings agree with the Shetland rock-
pigeon ; in the other the croup, except near the root of
the tail, is blue, and the wing coverts are chequered.
They thus may be said to illustrate the whole range of
variation in the colour of the croup and wings in the
wild rock-pigeon of Europe and Asia. The bird with
the white croup has several white feathers about the
head, and it thus departs from a typical wild bird ; but
the one with a blue croup is in its coloration the image
of a chequered rock-pigeon.

In the bird with chequered wings we have complete
reversion, not to the blue rock of Europe so much as to
the blue rock of India. The explanation of this may be
that the ancestors of both the fantail and the owl were
Indian, or at least Hastern birds. If this is so the
reversion in the case of the darkest bird is all the more
complete and remarkable.

Having referred to the reversion in colour, the question
remains, is there reversion also in form? Weismann, it
will be remembered, took for granted that Darwin’s
fantail-barb-spot cross was ‘‘a mere case of reversion as
regards the coloration of the plumage,” and pointed out
that “reversion to the blue colour is not necessarily
accompanied by a reversion to all the other characters of
the ancestral form.” In the case of my most typical
bird there is, as far as an external examination can show,
practically complete reversion. In its measurements it is
relatively almost identical with a typical Shetland blue
rock. I say relatively because, having only reached
maturity, it is not yet full-grown. In its extreme length
it is 2 per cent. shorter than a full-grown Shetland bird,
and this amount of difference may be said to obtain for
the legs, beak, toes, &c.

In its attitude and movements it resembles the wild

XXVIil GENERAL INTRODUCTION.

rock-pigeon. If there is any difference it is in the tail.
There are the typical number (twelve) of tail feathers,
and the outer margin of the outermost feather at each
side is edged with white, except near the tip, but the
feathers at each side of the middle line have their inner
edges very slightly tilted upwards. This is the only
hint of the highly specialised nearly upright fan-like tail
of the white sire.

From these experiments with pigeons it is evident that
the reversion may be partial or all but complete in form
as well as in colour. In the case of the white fantails
there is partial reversion in colour only ; in the case of the
white fantail and the blue pouter—two well-marked and
long-established breeds—the struggle amongst the parts
ended in the production of a bird taking after the one
parent in its colour and the other in its form ; with the
owl and archangel there was considerable reversion to-
wards the blue rock, but, perhaps because the archangel
is a comparatively recent production, none of its characters
could be detected in its cross-bred offspring ; in the case
of the white fantail and owl-archangel cross there is
practically complete reversion in form as well as in colour.

Perhaps I may here say that reversion is more a
negative than a positive influence, that if I understand it
aright complete reversion is mainly due to the develop-
ment being abruptly arrested so as to reproduce a lost
ancestor. Sometimes several printings are required to
produce a coloured plate. Were one or more of the
printings omitted a kind of ‘reversion’? would be the
result. When the owl and archangel are crossed the
latest colours added by the fancier are not reproduced,
and the older and simpler colours are again made visible,
When the white fantail and owl-archangel were crossed
all the recently acquired colours were lost, and the common
ancestor of all our domestic pigeons was once more re-
produced. How the ancestral units of germ-plasm over-
come during development the less stable units represent-
ing more recently acquired peculiarities can only be
euessed at,

GENERAL INTRODUCTION. XXix

It will be remembered that Weismann thought it very
probable that Darwin’s barb-fantail-spot cross was
“essentially a mere case of reversion as regards the
coloration of the plumage.” In my owl-archangel-
fantail cross there is not only more complete reversion
as regards the coloration than in Darwin’s cross-bred
bird ; there is, as far as external measurements can show,
practically complete reversion as regards form, but more
remarkable still, there appears to be reversion as regards
the constitution and habits.

A successful and experienced breeder of sporting dogs
recently told me that close inbreeding for three or four
generations leads to marked senile degeneration. If,
however, there are any puppies in a grossly inbred litter
that take after a good ancestor several generations re-
moved, they invariably prove the strongest and best.
In the same way it is said that if an inbred sire and
dam produce a striped dun-coloured foal, it almost
always turns out well, and alike in hardiness, staying
power, and durability eventually surpasses closely re-
lated offspring of a grey, chestnut, or bay colour, That
highly bred, not very fertile, delicately nurtured parents,
with weak constitutions, should sometimes give rise to
vigorous prolific hardy offspring may seem impossible,
and yet a great many facts might be marshalled in sup-
port of this assumption. Reversion, in fact, seems to
lead to a form of rejuvenescence—due presumably to the
ancestral units overcoming and controlling the more re-
cently evolved and less stable units, which, if allowed to
have their way, would give rise to offspring bearing all
the marks of decadence that characterised the immediate
ancestors.

My “restored” blue rock looks as vigorous and hardy
and compact as a wild bird, and he is greatly admired by
fanciers alike for his carriage, form, and colour. He
seems to prefer sitting, when off duty, in a dark recess to
sunning himself, and alike im his movements and disposi-
tion he differs from his companions. He is shy, active
in his movements, and when disturbed seems to be not a

XXX GuUNERAL INTRODUCTION.

little concerned about the nest in which his hopes are at
present centred.

2. Fowls.—It is generally believed that the game breed
of fowls has sprung from one or more varieties of the
jungle fowl (Gallus bankiva), and that from the game all
the other domestic fowls have been derived. If this is
the case, and if there is any truth in the reversion
dogma, fowls when crossed should sometimes take on the
characters of either the game or the wild breed.

An unusually dark red-breasted game bantam hen was
crossed with an Indian-game-Dorking. The result was
nine chickens, six of which resembled Dorkings, while
three in their form and colour resembled game birds.
Two of the three, now they are full-grown, only essen-
tially differ from certain varieties of the wild fowl in
having a small double instead of a small singie comb—
the double comb having been inherited from the cross-
bred game-Dorking cock. These game-like, cross-bred
birds are especially interesting because they are very shy,
and fly about like wild birds. ‘There has thus, in this
case, been a marked reversion, not only in form and
colour, but also in disposition and habits—a not uncommon
thing in cross-bred animals.

3. Dogs.—All the breeds of dogs are probably gene-
tically related to the wolf, yet I never heard of a cross
being obtained that as closely resembled the wolf as cross-
bred pigeons occasionally resemble the wild rock-pigeon,
This is perhaps partly because the wolf is not the only
wild ancestor, and partly owing to the majority of the
most familiar breeds being inbred. All that can be ex-
pected of dogs is that they should revert to one of the
less remote ancestors, Just as the offspring of the blue
fantails reverted to their comparatively recent white
ancestor. When colour alone is considered, the Dal-
matian breed may, I think, be looked upon as the most
highly specialised ; to wolf-hke dogs it stands in the
same relation as the zebra does to dun-coloured horses.
Dalmatians have probably sprung from pointer-like pro-
genitors, and being comparatively uncommon they are

GENERAL INTRODUCTION. XXX1

as a rule inbred. Hence, from an extreme cross with
a Dalmatian, instead of wolf-coloured or even whole-
coloured offspring, we should expect the progeny to
approach in colour the Dalmatian’s less remote ancestors,
v.e. we can only look for partial reversion. I crossed a
Dalmatian (one of the lighter varieties) with a well-bred
sable collie, and obtained three pups. The pups (which
died when quite young and were preserved in spirit)
neither resemble young collies nor young Dalmatians, but
rather suggest young pointers or foxhounds. The ground
colour is nearly white in all three; in two there are five
large dark brown blotches, in one four lemon-coloured
patches. This seems to be a case of reversion towards
the medizeval ancestors of the Dalmatian.

4, Rabbits.—During the present summer I have bred
a large number of white rabbits by mating ordinary white
does with a smooth-coated buck. With two exceptions
all the young have resembled their parents. The one
resembles an Angora, the other as closely resembles a
Himalaya rabbit. The Angora might be looked upon asa
‘‘ freak ;” or seeing that it is the only one out of well-
nigh fifty rabbits by the white buck, it might be accounted
for by saying the doe must have numbered a long-haired
rabbit amongst her ancestors. The real explanation
doubtless is that the sire of this exceptional rabbit was
bred from an Angora rabbit, 7.e. the long-haired rabbit
is, as far as external characters go, an exact reproduction
of its paternal grandmother. The restored “ Angora”
is not so much interesting because the reversion is, as
far as it goes, complete, but because only one out of
nearly fifty rabbits by the same buck showed any signs
of reversion. I know of a similar case of reversion in
the human family. A man, decidedly lighter than an
octoroon, married a fair English woman. Of their two
children, one is like the mother, the other is quite as dark
as a mulatto.

The “restored”? Himalaya is even more interesting
than the Angora. It exactly reproduces the maternal
great-grandmother. But as one of the sisters of the sire

XXXil GENERAL INTRODUCTION.

had a dark muzzle it is conceivable some of the Himalaya
blood came from the paternal great-grandfather. Many
other instances of reversion in rabbits might be given,
some of which exactly agree with cases of reversion
commonly supposed to occur in the human family.

These rabbit experiments lend powerful support to the
view that a child may be the image of its grandmother,
or of its great-grandmother, while the new foal of the
Iceland skew-bald pony, to be further referred to, affords
very strong testimony in favour of the belief that a child
may be the image of its own mother.

That only one of the fifty descendants of the white buck
took after his dam (t. e. after their grandmother), while all
the others but one resembled his sire (i.e. their grand-
father), shows that experiments of this kind must be
conducted on a fairly large scale to be of any use. The
maternal grandparent was probably represented by ger-
minal units in all the fifty descendants of the white buck,
but only im one were they sufficiently potent or suffi-
ciently plentiful in the ripe male germ-cell, or sufficiently
lucky to obtain complete control during the co-mingling
of the units of protoplasm that accompanies and forms
the essential part of fertilisation.

Two reflections that flow from a contemplation of the
solitary ‘“ restored’? Angora may, though somewhat out
of place, here be mentioned. The first is, had the doe
of the solitary young Angora been previously mated with
an Angora buck, she would probably have been cited
as a case of “infection,” provided of course the breeding
of the buck had not been recorded.

The other reflection may take the form of a question.
If only one out of fifty (7. e. 2 per cent.) of the offspring
take after the grandmother, how many of the offspring
(supposing there is such a thing as telegony) might be
expected to take after the previous sire, whose influence
must presumably count for infinitely less than that of an
ancestor only one generation removed ?

I think the answer might be, at least for rabbits, not
more than 1 per cent. of the offspring. It will be re-

GENERAL INTRODUCTION. XXXil1

membered that Romanes in describing telegony says, ‘“ It
is so rare that I doubt whether it takes place in more
than 1 or 2 per cent. of cases ;’’ adding, however, that
“nearly all my professional correspondents would deem this
an absurdly low estimate.’? Evidently, should the fact
of telegony be proved, it will be necessary to determine
as accurately as possible whether it is a very rare or a
comparatively common phenomenon.

5. Ducks.—Another interesting case of reversion may
be mentioned. A cross between a common wild duck
and a black Cayuga drake produced during the present
summer to a common wild drake seventeen ducklings.
Of these nine are like the black Cayuga grandsire, while
eight take after the wild drake—the immediate sire.*

6. Horses——I may here mention several instances of
apparent reversion in the Equide.

(a) Teeth.—The ancestors of the horse had seven cheek
teeth—four premolars and three molars—on each side of
the upper jaw. The recent horse has, as a rule, only
three (2—4) premolars. When a fourth (the wolf-tooth)
is present it is small, and usually soon disappears. In
zebras there are often four premolars in the upper jaw,
and the first is sometimes nearly as large as in the extinct
three-toed horse Hipparion. ‘T'wo years ago I bred a bay
Shetland foal, having several distinct stripes on the neck
and shoulders, bars in the vicinity of the ‘“‘ knees” and
hocks, and, in addition, a distinct dorsal band. In this
foal the first premolar (wolf-tooth) was large—relatively
nearly as large as in Hipparion.

(b) Digits.—The biologist is as satisfied that the horse
has descended from five-toed ancestors as the astronomer
is that the earth moves round the sun, and he knows that
not very long ago, geologically speaking, all horses had
three complete digits encased in three separate hoofs.
The digits borne by the fore-limb corresponded to the
fore, middle, and ring fingers in man, the hind digits to
our three middle toes. As I pointed out some years ago,

* To Alexander Cowan, Esq., of Woodslee, Penycuik, I am indebted
for the information about the ducks, and for various other friendly deeds.

XXXIV GENERAL INTRODUCTION.

the horse is still for a time tridactylous. In a four-
weeks horse embryo there are no rudiments of digits in
the paddle-shaped limbs, but in a five-weeks embryo
there are rudiments of three digits, and at six weeks the
foot is a miniature of that of the rhinoceros.* The
second and fourth digits in the embryo horse, though
small, are almost as complete as in Hipparion, the three-
toed fossil horse preserved in large numbers in the
Pikermi beds near Athens. As in Hipparion, the second
and fourth digits are asymmetrical. They thus, while
forming a nearly symmetrical pair, differ from the large
symmetrical middle digit—the only complete digit in
recent Equide. Occasionally a foal is born with two
hoofs on one or more of its limbs; at very long intervals
w foal appears with three hoofs on one or more of its
limbs. Alexander’s Bucephalus, e. g., was polydactylous,
us was Cesar’s favourite horse. I have in my possession
four specimens showing extra digits in the horse. Poly-
dactylism is not uncommon in man, and it seems to be
still more common in the pig. In man the extra digits
seem to be always due to the splitting either of the
thumb or of one or more of the fingers. In one of my
polydactylous horse limbs the extra digit is without doubt
due to the splitting of the third or middle digit. The
extra digit in the three remaining specimens is, however,
not so easily accounted for. When the large middle
digit splits, the two resulting digits are almost identical
in form if not in size. In my most complete specimen
one of the digits—the inner—is not only very much
smaller than the other; it, like the inner digit in Hip-
parion, is asymmetrical, and the articulation between the
first and second phalanges (the first and second pastern-
bones) has been obliterated. The smaller inner digit is
thus far from being an image of the large functional one;
hence it does not seem to have been formed by splitting

* The horse, hence, does not during development, as some imagined,
pass through a five-toed stage, 7.¢. it is never, even when a very small
embryo, pentadactylous like its supposed remote ancestor Phexacodus, in

which the skeleton of the fore-foot is, in many ways, wonderfully like ise
of the human haud.

GENERAL INTRODUCTION. XXXV

or dichotomy. But if the extra digit has not in this case
been split off from the large middle digit, its existence
cun only be accounted for in one of two ways. It is
either a sport—an instance of abrupt or discontinuous
variation—or a restoration of one of the digits found in
the three-toed ancestors. Seeing that the horse embryo
starts with three toes, and that the lateral digits persist
in a nearly perfect though minute form for several months,
it seems to me more natural to account for the occasional
presence of an asymmetrical extra digit, such as occurs in
some of my specimens, by the reversion theory than by
any other. As it happens, in the inner (second) digit of
the embryo horse I especially examined some years ago
the first and second phalanges had all but united. Had
this embryonic digit been favoured from the first by an
unusual amount of nourishment, it might have increased
to form a large extra digit instead of degenerating to
form a mere vestige (the “‘button’’) at the end of the
inner “splint”? bone. If in some cases the extra digits
in the horse correspond to digits which persisted in the
horse family well through the tertiary period, these digits
form a very striking instance of reversion.

(c) Forearm.—Keeping to the fore-limh, still another
case of reversion may be mentioned. In the ancestors of
the horse, as in ourselves, there were two distinct bones
in the forearm, the radius.and ulna. In all the works
dealing with the skeleton of the horse the ulna is de-
scribed as incomplete. It is said to terminate in a slender
process some distance from the lower end of the radius.
In very young horse embryos I find the ulna is not only
as complete, but nearly as large as the radius. But it is
often complete, though not entirely ossified, in foals, and
occasionally complete in the adult. In the skeleton of
the horse placed by Sir William Flower in the entrance
hall of the Natural History Museum, London, there is a
complete ulna, and in all horses the lower end.of the ulna
persists and enters freely into the wrist (‘knee’’) joint.
In having at times a complete ulna in the horse we have
another instance of reversion.

XXXVI GENERAL INTRODUCTION.

As the whole question of reversion involves a general
acquaintance with animal pedigrees, I may, before re-
ferring further to my horse embryos, say a few words
about what is usually known as the Recapitulation Theory.
In the making of a breech-loading hammerless gun, a
piece of wood is gradually fashioned into a stock, and
various kinds of metal are manipulated in diverse ways to
form the lock and barrels. From the first it is evident
what the workmen are about. But if a gun were con-
structed on the plan followed by nature in the making of
a mammal, the procedure would be very different. The
egun-inaker (who would require to be a miracle worker as
well) would go to work in some such roundabout way as
the following. Starting with a piece of clay, he would
set about transforming it into flint, but before completing
the process would convert it imto something remotely
resembling a boomerang or a knob-kerry. By further
legerdemain the “throwing stick”? would become a
cross-bow, and this, by a long and intricate series of
transformations, would assume, or all but assume, in turn
the characters of a flint gun, various kinds of muzzle-
loaders, and breech-loaders with hammers. Eventually it
would take the form of a hammerless ejector.

In no Vertebrate is the development direct, however
rapid it may be. For example, the horse, an all but in-
visible speck of protoplasm to start with, passes at the
outset through a series of remarkable changes (which so
far can only be guessed at), to emerge at the end of the
third week as a somewhat fish-like creature almost bent
double over a large active heart. The tail is bilobed,
like that of a mermaid (manatee), but neither limbs nor
jaws have yet appeared. A mammal at no stage can
make use of gills, yet the horse embryo has, for a time,
three pairs of gill pouches. A quarter of an inch lone at
three weeks, the horse embryo is half as long again at
four weeks. It might, at this stage, pass for a human
embryo of a similar age. There are paddle-hke limbs
and a lizard-lhke tail many times longer than the les,
At five weeks the limbs are still paddle-like, but in each

GENERAL INTRODUCTION. XXXVit

paddle the foundations of three digits (2, 8, and 4) have
appeared. A week later the fore-limbs are longer, have
undergone rotation inwards, and the three digits in each
are more distinct. The jaws have now appeared, and
there is no longer any indication of gill pouches. In
the six-weeks horse (though under three quarters of an
inch in length) we have a partial restoration of the
earlier three-toed ancestors of the Equide, but ere the
seventh week is reached all external indication of the
outer (2 and 4) digits has vanished, and the single re-
maining digit (3) is beginning to assume the characteristic
equine form. By the end of the eighth week, though
the embryo is barely two and a half inches in length, we
have in many ways a miniature horse, the limbs extended
as if ready for action, and the tail only reaching the
hocks. If at six weeks the cross-bow stage has, as it
were, been reached, by the eighth we have got as far as
a flint gun.

As it happens, these and other facts to be mentioned
presently have a bearing not only on the reversion theory,
but also on a subject attracting much attention at the
present time, viz. the origin of the three great groups of
Mammals. During recent years this subject has been
often discussed, and we seem to be drifting further and
further from the view that the higher Mammals (Hutheria)
have descended from the Marsupials—the opossum and
kangaroo group,—while they in their turn originated
from the egg-laying Monotremes, the group now repre-
sented by the duck-mole and echidna.

It may be more than a mere coincidence that, for a few
days, the horse embryo forcibly reminds one of some of
the young Marsupials. In nearly all Marsupials nourish-
ment up to the time of birth can only be derived from
food— uterine milk ”’—filtering into the yolkless yolk-
sac. This necessitates premature birth. In the opossum,
e.g., the young are transferred to the pouch as soon as
they can hang on to the teats. In the higher Mammals
and in certain Marsupials a more permanent plan is
adopted for the nourishment of the embryo. The embryo

XXXVIli GENERAL INTRODUCTION.

horse, during the first six weeks, is nourished like the
young opossum and kangaroo by “ uterime milk ” filtering
into the yolk-sac ; but beyond this period the foetal blood
is brought into close relation with that of its dam, and thus
a fresh food-supply is tapped. During the seventh week,
while the new machinery is being fitted up, the embryo,
uncertain as to its fate, behaves like a young opossum
when preparing for its life in the pouch. Few now sup-
pose that young opossums, wallabies (rock kangaroos),
and other Marsupials reach the pouch by crawling down
the teats. On the other hand, few seem to know how the
young wallaby, ¢. g., manages to glue itself so firmly to
the teat as soon as it reaches the pouch. At the end of
each teat (as Mr. le Souéf of Melbourne recently explained
to me) there projects a delicate tube. The female wal-
laby conveys the young as they are born by means of her
lips to the pouch, which is kept open during the process
by her short fore-lmbs. Even at this early period the
lips of the young, when stimulated, may contract ; at any
rate, the minute tube hanging from the end of the teat
gets into the mouth of the helpless youngster, and is
probably held in position for a time by the lips. The
lips, however, if active at this stage, would soon get ex-
hausted. ‘To prevent the young one slipping, the slender
tube at the end of the teat is distended, it is dilated so
as to fill the mouth, the result being that the young are so
firmly fixed that a considerable force is required to drag
them from their moorings, and when once removed it is
impossible to replace them. The dead or helpless embryos,
sometimes found lying in the pouch, have probably either
slipped from the lips of the mother or dropped from the
teat before the delicate terminal tube was inflated. In
the young Marsupial, it may be meutioned, the lips are
relieved from the business of sucking ; the milk is pumped
into their mouths by certain muscles compressing the
mammary glands.

It may seem a far cry from a new-born wallaby to a
seven-weeks horse embryo, but the distance may not be
so great as ib seems. Not only is the lower jaw in a

GENERAL INTRODUCTION. XXX1X

very backward state in the young horse at the end of
the sixth week, it is still greatly shorter than the upper
jaw at the beginning of the forty-seventh day. Evidently
during the last two days of the seventh week the develop-
ment of the structures around the mouth proceeds apace,
as if it were unexpectedly necessary to prepare the em-
bryo for premature birth, and for playing the part of a
helpless opossum. By the end of the forty-ninth day
the lower jaw decidedly projects beyond the upper,
the tongue is well formed and slightly raised from the
floor of the mouth, which is sufficiently open to show a
fair-sized, well-formed space between its roof and the
well-moulded tongue. A point of still greater interest
is that both the upper and lower lips are so notched that,
if approximated, a gap would be left about the size of
the slender terminal portion of the teat in a Marsupial.
Another point is that, as the lips rapidly develop, rudiments
of the vibrissee (sensitive hairs) make their appearance
around the muzzle. As I said before, all these changes
taking place about the time the horse would presumably
be born were it a Marsupial may be a mere coincidence,
and quite meaningless. They may, however, point to a time
when the ancestors of the horse were as primitive as some
of the Australian Marsupials are to-day, to a time when
they were prematurely ushered into the world in a per-
fectly helpless condition ; and they may further indicate
that, if the higher Mammals (the Eutheria) have not
actually sprung from amongst the Marsupials, they and
the ancient Marsupials travelled for a time along nearly
parallel lines. If this is the explanation, it follows that
at the end of the seventh week (when the horse embryo
is little over an inch in length) we have an extremely
interesting example of recapitulation, a kind of embryonic
reversion. Evidently it is but a passing phase, for ere
the eighth week comes to an end the mouth is tightly
closed—the lower lip partly overlapping the upper at each
side—and the eyes are also closed. The eyes, I might
have mentioned, are widely open during the whole of the
seventh week.

xl GENERAL INTRODUCTION.

Before leaving the subject of reversion I may refer to
a hinny (jennet) recently added to my stud. This young
hinny (a cross between a bay Welsh pony stallion and a
common ass) is of a yellowish-brown colour—the colour
of the wild horse of the Dzungaria Desert—and has
distinct bars at the ‘‘ knees’? and hocks, as well as a
dorsal band and a shoulder stripe. The leg bars are
evidently due to reversion, as no leg bars are present in
either of the parents. Reversion of this kind is very
common in mules, and is not unknown amongst pure-bred
asses and zebras. A zebra foal, e.g., born during the
present summer in the Regent’s Park gardens, London,
is striped to the hoofs, and is in other respects like the
zebra named after Mr. Selous. In the parents, which
belong to the Chapman variety, the legs are only partially
striped. Several of my hybrids have more bars on their
legs than their sire.

From what has been said as to reversion, it is evident
that breeders should in all cases direct as much if not
more attention to the ancestors than to the parents of
their breeding stock, that they should expect and make

ce

allowance for reversion, for ‘‘ regression towards medio-
crity,’* especially remembering that the more unlike the

parents the greater is likely to be the reversion in the

0%

offspring, and that the latest acquired peculiarities are
hkely to go first unless they have been “ fixed” by
inbreeding, or are of the nature of ‘ sports,”

As indicated in the last of the three papers, it has
been the fashion for some time to throw doubt on the
reversion hypothesis. It has been stated that “around
the term reversion a singular set of false ideas have
gathered themselves.’t But statements of this kind
do not disprove reversion. Even if the hypothesis in
question has been invoked to account for the appearance

* Kvidently the more inbred and closely related the parents the more
limited will be the range of reversion, but still even in grossly inbred stock
reversion will occasionally occur, especially to prepotent, and not very far
removed ancestors. Y

+ Bateson, ‘Materials for the Study of Variation,’ p. 76.

GENERAL INTRODUCTION. xhi

of new forms which were either sports or the product of
discontinuous variation, it does not follow reversion never
occurs. I think it must be admitted the pigeon and
rabbit experiments go a long way towards proving the
fact of reversion, and the more I contemplate my zebra
hybrids the more convinced I am that they are neither
new creations in the strict sense of the term, nor yet
intermediate forms ; and if they are neither the one nor
the other, they must be more or less accurate restorations
of their comparatively remote ancestors. The heredity
problem is sufficiently difficult as it is, but if we are
debarred from invoking the assistance of the reversion
hypothesis it will become hopelessly incomprehensible.
In conclusion, I may point out that even from a practical
point of view reversion is of extreme importance, for it
indicates how in some cases varieties and breeds which
have through inbreeding undergone senile degeneration
may be regenerated without the loss of their best and most
prized characteristics.

2. Prepotency and Inbreeding.—More than thirty years
ago Darwin recognised that ‘‘ the subject of prepotency
is extremely intricate.’ It must be admitted this intri-
cacy continues, and is likely to continue until the laws of
heredity are better understood. Amongst the other dif-
ficulties we have to contend with, there is the impossi-
bility of determining the amount of prepotency in any
given race or individual, and the fact that prepotency
may altogether escape detection, or exist through gross
inbreeding where it is least expected. The leader of any
given wild herd may be decidedly prepotent, but unless
he is mated with the members of some other herd pre-
senting different characters the prepotency may escape
notice ; and again, the members of any given séction of a
species may, through inbreeding, be highly prepotent,
while the members of the other sections (owing to abun-
dant facilities for intercrossing) may be non-prepotent.
What is true of individuals may be true of races and
varieties. The Jews, as a race, are more prepotent than
the English—are better or purer bred; but the prepo-

d

xlii GENERAL INTRODUCTION.

tency only declares itself when intermarriages take place.
On the other hand, any given member of a non-prepotent
race may, through inbreeding (sib-breeding), be more
prepotent than any given member of a decidedly prepo-
tent race. Hitherto prepotency has almost invariably
been associated with inbreeding, and many believe not
only that it can be induced by inbreeding, but that apart
from inbreeding it is impossible. On the other hand,
sports * and certain marked variations are often prepo-
tent, 7. e. they resist the swamping influence of inter-
crossing, and hence it would be difficult to prove in many
cases that prepotency has not originated with, or is an
attribute of, sports. Mr. Galton has recently gone
further than this, and given it as his opinion that prepo-
tency is, in itself, a sport; to use his own words, “ high
prepotency does not arise through normal variation, but
must rank as a heritable sport or aberrant variation.” t
That sports are frequently prepotent has been placed
beyond doubt, but that prepotency is in itself a sport
has not yet been proved. When we are able to account
for prepotency, why any given variety is able to with-
stand the swamping influence of intercrossing, we shall,
I think, be nearer an explanation of the origin of
species.

Mr. Galton, in his suggestive paper on prepotency, says
nothing about interbreeding. Perhaps, while believing
“high prepotency”’ rapidly acquired is due to an aber-
rant variation, he will be prepared to admit that a lower
grade of prepotency may be induced by inbreeding. I
believe inbreeding is common amongst wild animals, and
that by inducing prepotency it plays an important part
in the origin of species. Variation is of fundamental

* A sport is an abnormal or aberrant variety the result of sudden and
pronounced variation in one or more directions. The horse compared with
a dog, or its old enemy the woll, is a poor jumper. If a horse were
suddenly to appear that could leap nearly twice its own height it would be
a sport, as would be a horse with extremely short legs or without a tail.
An upright mane might either be a sport or the result of reversion, while

a hairless horse would be considered a sport.
+ Nature, July 14th, 1898.

GENERAL INTRODUCTION. xh

importance ; the destruction of the unfit is also important ;
but simple variation and the survival of the fittest, unless
sterility or prepotency is implied, are not sufficient to
account for the origin, from a few simple forms, of a
countless number of plants and animals, many of them
amazingly complex in organisation. The need of some-
thing above and beyond variation and natural selection
was especially recognised by the late Mr. Romanes. In
what he termed physiological selection he believed he
had found the additional factor, physiological selection
being something by which isolation was secured, which
made sure that some of the varieties so abundantly pro-
duced in nature would have a chance of perpetuating
themselves, 7. e. escape being swamped by intercrossing.
In the case of the domestic animals the breeder plays the
part of the additional factor; by isolation he prevents
intercrossing. Without fences the famous breeds of cattle
that have been so carefully built up would, unless highly
prepotent, soon cease to exist as distinct breeds, and
would ultimately be merged through intercrossing into
as many varieties as there are distinct or isolated areas.

Hitherto the explanation of one variety persisting
while others, equally fit in every way, vanished, has
sometimes been that the members of the more fortunate
variety, while fertile with each other, were sterile, or at
least less fertile, with other varieties and with the parent
species. It is, of course, conceivable that some sports
are sterile except amongst themselves, just as some sports
are prepotent, but satisfactory evidence of this is still
wanting. The explanation which prepotency affords does
away with the need of sterility, and it does away with the
need of rigid isolation, with naturai barriers or fences,
because the prepotent forms have so much “ character”
that, however mated, some of the offspring inherit their
own structural and other peculiarities.

What, it may here be asked, do we understand by
prepotency and interbreeding? Any animal, male or
female, which strongly impresses its own peculiarities of
form, colour, disposition, &c., on its offspring, is pre-

xliv GENERAL INTRODUCTION.

potent, while animals that are the offspring of more or
less intimately related parents are interbred,—when the
parents have been closely related for several generations
they are said to be grossly inbred. There is, however,
nothing absolute about either prepotency or inbreeding,
they are relative terms. An animal (male or female) may
be prepotent in some respects and not in others (and this
whether the prepotency has been acquired by inbreeding
or through a “sport ”’), or prepotent with one mate and
not with another, prepotent one year but not the next,
because prepotency is of necessity subject to the influence
of variation and reversion, and also doubtless to nutrition
—more especially of the germ-plasm prior to fertilisation.

Prepotency, when associated with useful characters, is
highly beneficial, while inbreeding is often a doubtful
heritage. Nature only tolerates inbreeding up to a cer-
tain point, for while it may assist in perpetuating useful
characters by inducing prepotency, it often does this at
the expense of vitality—it may be of fertility as well.
It is conceivable that inbreeding has played an important
part in the extinction of species ; it has undoubtedly been
the means of deteriorating, if not actually destroying,
many of the breeds and varieties artificially produced.
A carefully conducted series of experiments, showing the
effects of inbreeding on various kinds of animals, is still
greatly needed. When such a series is forthcoming it
will be time enough to discuss at length the physiology
of inbreeding. Still, something further may well, at this
stage, be said about inbreeding and prepotency. It will,
I think, be admitted that prepotency may be due to
either natural or artificial causes, or be partly due to
both. In nature, prepotency may (1) arise spontaneously
and abruptly along with sports in one or more directions,
or gradually with the help of natural selection—whether
it may arise as a special variation apart from a sport, as
Mr. Galton seems to think, I am not prepared to say ;
(2) it may be gradually acquired when a few individuals
of any given species or variety are so isolated that in-
breeding is inevitable. Artificial prepotency may be

GENERAL INTRODUCTION, xlv

slowly induced by inbreeding, but I doubt if prepotency
can be rapidly produced artificially apart from inbreeding.
It may therefore be taken for granted that interbreeding
(1) induces prepotency by fixing the characters of the
particular variety selected ; (2) in as far as it prevents or
at least limits intercrossing it diminishes the chance of
reversion on the one hand, and restricts the range of
variation on the other, thus tending to maintain un-
diluted the distinctive characters of the type. But it must
be added, inbreeding, while keeping the “blood” pure,
tends to weaken it by diminishing the vitality of the breed.
Prepotency, on the other hand, however acquired, alike
in nature, on the farm, or in the dovecote, tends to arrest
or neutralise the swamping effects of intercrossing.
Some breeders say they can produce a horse so pre-
potent, so fixed by interbreeding, that it will produce its
like however mated. A famous breeder of high-class
ponies once boasted that he had a filly so prepotent
through inbreeding that though she was sent to the best
Clydesdale stallion in Scotland she would throw a colt
showing no cart blood—provided the Clydesdale was not
‘also the product of inbreeding. Nature might make a
similar boast, the essential difference being that while in
the one case misfits and “‘ weeds ” are usually preserved,
in the other they are ruthlessly destroyed and buried out
of sight—in the struggle for existence the inbred
“‘ weeds ”’ go to the wall.

The careful observer soon recognises that all through
animated mature the greatest effort is made to secure
rejuvenescence. In the animal kingdom, and largely in
the vegetable also, this renewal of youth, without which
vigorous life is impossible, is secured by intercrossing or
cross-fertilisation.* The ingenuity displayed by plants
and animals to secure cross-fertilisation is simply mar-

* There is obviously no real difference between cross-fertilisation and
intercrossing. Whether we interbreed or intercross, engage in ‘‘line”
breeding or “‘cross”’ breeding, we are making use of cross-fertilisation.
Further, I may add the difference between intercrossing and hybridising
is one of degree, not of kind.

lvi GENERAL INTRODUCTION,

vellous. What a different world ours would be had it
been peopled from first to last with sexless forms, with
millions of virgin females! The antithesis of inter-
crossing (cross-fertilisation) is interbreeding (inbreeding).
Hence when we grossly inbreed we do our utmost to arrest
nature’s supremest effort; for though all the elaborate
and intricate mental and physical processes are comphed
with when close inbreeding is practised, there is little or
no real intercrossing. In inbred herds, e.g., the males
and females are so like each other that the offspring,
were it possible, might almost as well be raised by buds
or cuttings. In inbreeding the letter of the law is
observed, but not the spirit. In proof of this take the
case of the celebrated one thousand guinea bull “ Comet.”

‘ Herd-book’ tells us that “ the bull ‘ Bolingbroke ’
and the cow ‘ Phenix,’ which were more closely related
to each other than half-brother and sister, were coupled,
and produced the bull ‘ Favourite.’ ‘Favourite’ was
then coupled with his dam, and produced the cow ‘ Young
Phoenix.’ He was then coupled with his own daughter
(‘Young Phcenix’), and their produce was the world-
famed ‘Comet.’ ”? It must be admitted there was very
little intercrossing in the case of “ Comet,’ there was
still less in ‘ Clarissa,” the dam of the celebrated cow
“Restless,” and, as a matter of fact, many breeders do
their utmost to do away with intercrossing ; they act as
if they thought nature in introducing intercrossing had
blundered. This applies to fanciers and to breeders of
horses and sheep as well as to breeders of cattle. A
writer in the Field of April 9th, 1898, tells us he had
heard ‘ Mr. Joseph Osborne, the iilest authority living
on British thoroughbreds, declare that you cannot now
get too much of Bitdeataher But cross-fertilisation, it
may be mentioned, not only serves to maintain the organs
and tissues of aiaate and animals at a high state of
efficacy ; it fosters if it is not the prime cause of varia-
tion. It is conceivable in some planets less favoured
than our own the plan of cross-fertilisation has not yet
been arrived at, or, in transcendental language, has not

GENERAL INTRODUCTION. xlvii

yet been introduced. Chaos may still reign in certain
parts of the universe, and instead of a great variety of
plants and animals there may be but a bathybial-like
layer of protoplasm—a rind of living seething slime, or,
at the most, countless numbers of simple unicellular
organisms. In such a case the introduction of cross-
fertilisation or its equivalent would work miracles more
wonderful than the making of dry bones live. In the
case of our own planet untold ages may have elapsed
before the raw material of life was capable of benefiting
by the elevating influence and resuscitating power of
rejuvenescence or cross-fertilisation.

But while exalting the influence of intercrossing—one
of the most potent and far-reaching of all the vital forces
in nature—it is well to remember that, as already hinted,
by intercrossing alone, even with the aid of natural selec-
tion—with some means of getting rid of the “unfit ”’ or
useless variations—the conditions which now prevail in the
animal and vegetable kingdoms could never have been
reached. Interbreeding (inbreeding) may have ably
seconded intercrossing in the origin of species. For
though inbreeding in excess saps the life-springs, and
leads to decline, degeneration, and death of the species,
perhaps, as well as of the race, it may (under the control
of natural selection) be the means of giving certain types
or varieties a chance of surviving,—in a word, inbreeding
may counteract the levelling, if not regressive tendency
of cross-fertilisation—may arrest as with a wall the
“swamping effects of intercrossing.” As breeders and
fanciers select, and with the help of inbreeding fix, from
amongst the varieties so plentifully provided, such as they
consider most useful or most beautiful, so in nature the
varieties that pass in the severe competition that every-
where prevails may be fixed by inbreeding, and have a
chance of, in course of time, forming new species. It
thus appears that interbreeding may serve as a check to
intercrossing, that while intercrossing tends to give a
new lease of life, and at the same time favours the
appearance of new varieties, interbreeding tends to fix

xlviil GENERAL INTRODUCLION.

and perpetuate certain varieties, though when carried too
far it not only arrests variation, but diminishes vitality and
makes for senility and degeneration.*

It is not hard to understand that a new individual,
developed from the union of two germ-cells from dif-
ferently constituted individuals, should more or less differ
from his parents and all their ancestors. Neither is it
difficult to understand how the offspring of closely re-
lated parents sprung from closely related ancestors should
be almost the image of their parents. But it is not so
evident why inbreeding should lead to loss of vitality or
to senility. The explanation seems to be that the stuff
of which animals and plants are made—the living clay or
protoplasm—has a limited lease of life, is only capable of
giving rise to a limited number of generations unless
revived or rejuvenated, unless “fresh blood” is intro-
duced.

Remarkable evidence of this has recently been forth-
coming from amongst the Protozoa—the group which
includes the simplest and smallest living animals. Some
of the infusorians multiply by simple division. Like a
single colourless blood-corpuscle, one divides into two,
each again divides, and so on the process goes, but not
indefinitely. here comes a time when the process of
division is arrested, ‘senile degeneracy ”’ sets in, and the
new individuals, incapable of feeding or growing, soon die.

oO)

If, however, an exchange of protoplasm is occasionally

* Inbreeding is often said to lead to “atavism.’’ If atavism and
reversion or regression are considered one and the same thing, then I con-
sider ita mistake to say inbreeding induces atavism. Inbreeding almost
invariably leads to degeneratipn, which is quite a different thing from
regression. Cross-breeding, in virtue of reversion, may restore all the
vigour and vitality of the lost founders of some of our degraded inbred
herds. Neither hybrids nor half-breeds nor mongrels are necessarily
degenerate; they are usually intelligent and vigorous enough, while inbred
animals may be physically feeble, and mentally on the level of imbeciles or
idiots. The individual in an inbred litter of puppies which shows most
evidence of reversion is sometimes the only survivor; he is invariably the
most vigorous. In the same way, a horse bearing the ancestral colours is
often as hardy as a mule.

GENERAL INTRODUCTION. xhx

allowed, if what is technically known as rejuvenescence
occurs at intervals, infusoria multiply indefinitely ; they
become, in a sense, immortal. The protoplasm making
up the organs and tissues of any two closely related
animals is of necessity almost identical. When such
animals are mated cross-fertilisation can hardly be said
to take place, and if this is repeated again and again the
individual cells (the germ-cells included) doubtless degene-
rate in very much the same way as the unicellular infuso-
rians when prevented from conjugating. The result in the
highly organised multicellular animal is likely to be the
same as in the simple unicellular, viz. senile degeneration
of the cells forming or destined to form the organs and
tissues.

In these days, when nothing is taken for granted, the
baneful influence of gross inbreeding is sometimes doubted,
and some are not even satisfied that inbreeding leads to
prepotency. It may therefore be well to give some
instances of the effects of inbreeding.

Bakewell, Webb, Colling, and Bates were among the
first advocates of inbreeding. One of their followers
was Amos Cruickshank. After a time Cruickshank dis-
covered inbreeding had been carried too far, his fine herd
of cattle was threatened with destruction, and he wisely
resorted to intercrossing to rejuvenate his degenerating
stock by the introduction of fresh blood. Why a little
“new blood,’”’ it may be froma herd living under almost
identical conditions with the dwindling one, should have
so profound an influence has not yet been explained.
When we discover why an exchange of molecules between
two infusorians at an interval of about two hundred
generations is sufficient to arrest degeneration, we shall,
perhaps, understand why the occasional introduction of
“new blood,” or of the same blood from, say, over the
seas, may prove the salvation of a herd.

There is abundant evidence that inbreeding leads to
prepotency. One or two instances may, however, be
given. The Dalmatian dog already mentioned is inbred,
as indeed are most Dalmatians. When bred with a pedi-

1 GENERAL INTRODUCTION.

gree collie, the result was, as already stated, three pups
with a white ground colour like the sire, and several
large blotches such as presumably characterised the sire’s
ancestors. In this case the prepotency of the Dalmatian
is so marked that the collie can hardly be said to be
represented in the offspring. A still better imstance of
inbreeding in hounds is given by the late Sir Everett
Millais. Sir Everett crossed a bloodhound with a
typical tricoloured basset dog. The half-breeds were
bassets in form, but not quite bassets in colour. When
these crosses were bred with a male basset, the majority
of the pups presented both the form and colour of highly
bred bassets. It may be mentioned that the bassets are
bloodhounds with short crooked legs, and that the
English bassets have all descended from a few indi-
viduals imported from France not many years ago. They
are all decidedly inbred. Hence, although the blood-
hound used was inbred and of an older type than the
basset, the offspring were in form bassets. Evidently
Sir Everett believed that had the bloodhound dam been
less inbred the crosses would have been from the first
bassets in colour as well as in form.*

It seems to be generally admitted that British cattle
have mainly descended from the ancient Celtic short-
horns, from Chillingham-like cattle introduced by the
Romans, and from longhorns imported from Holstein, &c.
Whether this be so or not, there is no evidence that any
of the less remote ancestors of our modern cattle were
hornless ; there was a time, doubtless, when the repre-
sentatives of our cattle, sheep, deer, and antelopes were
all hornless, but that was a very long time ago. It
follows that the polled cattle of to-day are recent pro-
ductions ; whether they are sports or reversions we need
not wait to consider. When long-horned Highland

* Sir Everett Millais, who worked long with highly bred stock, points
out some of the evils of inbreeding. He says of inbred dogs, distemper
carries off about 60 to 70 per cent. of those attacked, and that in breeding
to type we too frequently bring about hereditary deformity, rickets, and
other diseases.

GENERAL INTRODUCTION. li

heifers, such as may be seen any day in large numbers
at Poltalloch, Argyleshire, are crossed with hornless
Galloway bulls, the offspring are not only hornless, but
sometimes so like Galloways that they are with great
difficulty distinguished from pure-bred Galloways. This
is again the result of inbreeding ; the older race counts
for nothing in the presence of the inbred black Galloways
with no pedigree worth mentioning in the presence of the
long-horned Highlanders. When two inbred strains are
crossed the result is rather curious; e.g. when white
shorthorns and Galloways are crossed the offspring are
almost invariably blue greys and hornless: in this case
the prepotency of the Galloway, though still predomi-
nating, is considerably diminished by the inbreeding of the
shorthorn,

The Iceland skewbald pony, already mentioned, is also
a strikmg instance of inbreeding. She first of all pro-
duced a light bay foal to a pony of her own kith and
kin,—a pony presumably more inbred than herself.
Her next foal was the hybrid ‘“‘ Heckla,” a dark dun,
indistinctly striped, but without the smallest patch of
white anywhere. This summer her foal, to a bay Shet-
land pony,* is almost the exact image of herself, not
only in make and colour, but in the shape and position
of the rather peculiarly arranged vellowish-brown patches.
Evidence, apparently trustworthy, of the evils of inbreed-
ing will be found in Mr. Low’s great work on the
‘Domesticated Animals of Great Britain.2 He says a
gentleman experimented with foxhounds on a large scale,
with the result that through inbreeding “the race actually
became monstrous and perished.”’ The same happened
with hogs. After a few generations they became dimin-
ished in size, the bristles were changed into hairs, the
limbs became short and feeble, the fertility was diminished,
and the mothers were unable to nourish their young. Low

* To this bay pony three bay mares had bay foals, and a black mare had
a chestnut foal, but a piebald mare had a piebald foal. The Iceland ponies
are probably more inbred than the ordinary Shetland ponies, ¢.e. the ponies
not in the Shetland stud-book.

li GENERAL INTRODUCTION.

adds, “If the experiment be carried as far as the case
will allow, the feeble and frequently monstrous offspring
will be incapable of being reared up, and the miserable
race will utterly perish.” From what takes place with
guinea-pigs I think these statements may be at once
accepted as trustworthy; nevertheless it is desirable
that the experiment with hogs be repeated, and a com-
plete record of the results published.

I am not aware if any corresponding experiments have
been made with horses, unless, indeed, the breeding of
race-horses may be looked upon as a colossal and costly
experiment of this kind. It seems to be generally
admitted that English race-horses are inbred. Sir Walter
Gilbey speaks of their inherent galloping action and
speed as having been implanted “ by inbreeding during
nearly two hundred years.” * It may, however, be again
pointed out that there is plenty of inbreeding in nature,
and that the evils we associate with inbreeding may often
be counteracted by rigid and persistent selection, by pre-
venting the weaklings from leaving descendants. If in
staying power and constitution the modern thoroughbreds
are defective, it is not so much that they have descended
from a few imported sires, that they ‘“ trace their descent
to the Byerly Turk imported in 1689, to the Darley
Arabian imported in 1710, and the Godolphin Arabian
imported twenty years later,’+ as that the physically
“unfit”? as well as the “ fit” have often been allowed to
perpetuate themselves,— blood” and speed only having,
as a rule, counted in the selection alike of sires and
dams. The descendants of the horses that escaped from
the Spaniards after the discovery of America were rarely
found wanting in hardiness and general fitness, even
when small and unshapely; and in the same way the
descendants of modern thoroughbred sires now reared
under trying conditions in Montana are fit enough, though
often not larger than polo ponies. The cold and limited
supply of suitable food in winter, or the drought and

* © On Breeding Carriage Horses,’ 1898, p. 10.
7 Loe. ecit., p. 16.

GENERAL INTRODUCTION. lia

occasional scarcity of food during summer, as effectively
get rid of the weaklings and the overgrown individuals
as a prolonged dry season decimates the zebras, ante-
lopes, and other grass-eaters in Central Africa. It is not
difficult to realise how unfavorable surroundings would
systematically and persistently operate in the prairies and
savannabs in almost the opposite direction to that fol-
lowed by breeders of thoroughbreds. The process of
elimination would be mercilessly at work amongst the
foals, and proceed without rest or pause during colthood,
maturity, and old age.

The foals unable from the first to keep up with their
dams would soon perish, the colts that strayed would
often havea like fate, while both old and young, inca-
pable of withstanding periods of drought or other un-
favorable circumstances, would one by one drop from the
ranks, and fall an easy prey to the puma, jaguar, and
other flesh-eaters.

By the ruthless destruction of immense numbers—not
necessarily only the unfit, as we are too apt to take for
granted—the old troops would occasionally be broken up,
and new and differently constituted troops (including a
number of unrelated individuals) would be formed, with
the result that the evil effects of inbreeding would be
minimised, if not absolutely counteracted. A correspond-
ing destruction of the fit and unfit alike has, of course,
been impossible amongst our race-horses during the two
centuries that have elapsed since the introduction of
Byerly Turk.

I have been recently, in a small way, testing the con-
stitution of various breeds at different ages. Perhaps,
the conditions being somewhat unfavorable, the test has
been too severe. The plan has been to see how long
various breeds may safely be left out night and day in a
large field nearly 700 feet above the sea level, but sur-
rounded by woods and sloping on all sides from a central
plateau. Large sheds are available, and abundant food is
provided, A number of ponies continuously out during last
winter (1897-98) did extremely well. Amongst others

liv GENERAL INTRODUCTION,

were Shetland, Iceland, Norwegian, and Highland ponies,
a New Forest pony and her two-year-old mule foal, an
Exmoor pony, a half-Arab mare, and a small Clydesdale
mare. Four thoroughbred mares were rather the worse
than the better of being allowed out during the warmer
part of the day. A light cream-coloured, half-bred mare,
though apparently well in the evening of the 9th of
December, was found dead on the morning of the 10th,
apparently from a sudden chill. This mare (in foal to
the zebra) was in good condition, but, though she carried
a fairly heavy coat, she was thin-skinned,—very light
duns have probably weak constitutions. During the pre-
sent autumn (1898) I have had further evidence that
the thoroughbred constitution is very delicate. Harly
in August we had three cold, wet days. This was fatal
to a zebra-hybrid foal out of a three-year-old, small,
thoroughbred bay mare,—none of the other foals suffered
from this visitation of the east wind. Later in the
season three thoroughbred mares plainly showed the cold
was too much for them, and during the last week of
October a two-year-old and a yearling thoroughbred
completely broke down. So far (November) the three
yearling hybrids, the Clydesdale’s second hybrid foal, a
ten-year-old hybrid out of a zebra mare. a hinny foal
(born in July), a yearling out of a New Forest pony by
an Arab (Benazrek), an Iceland and a Shetland foal,
have all done extremely well, though continuously out
night and day. I am inclined to think that under 10 per
cent. of thoroughbred foals, and under 20 per cent. of
yearlings, would survive if exposed throughout the winter
in the vicinity of the Pentlands. In more genial sur-
roundings a larger number might survive, but they would
probably never reach a height of fifteen hands,

As a matter of fact, the English race-horse, compared
with even the Arab, is like a hothouse plant that only
manages to hold its own when forced and nursed with
enusan) care, and after all, except for covering very short
distances at a great speed, the majority of the humeesils
annually bred are of comparatively little use. Breeders

GENERAL INTRODUCTION, lv

flatter themselves that thoroughbreds have since 1689
increased on an average eight or nine inches (from 13:2
to nearly 15°3 hands), but they forget this was partly
due to the introduction of Arab blood, and that the size
of a horse is very much a question of selection, food, and
favorable surroundings. If the increase in size and
increase of speed have, as is alleged, been accompanied
by a diminution in the staying power and general fitness,
the gain can hardly be held to compensate for the loss.
That there has been a falling off in the thoroughbred may
be inferred from “ the smallness of the percentage of even
tolerably successful horses out of the prodigious number
bred at an enormous outlay.”’*

Two years ago thirty-two yearlings were sold for
51,250 guineas. ‘These thirty-two yearlings are repre-
sented by two winners of five races, Florio Rubbatino and
La Reine, who have contributed about £2000 to the total
cost ; and there is not, as far as can be known, a single
one of the remaining thirty with any prospect of making
a race-horse.’’+

When it is remembered that in the majority of English
races very little staying power is now needed, the failure
of the thoroughbred is all the more remarkable. If it is
true, as many assert, that the English race-horses are, as
a breed, on the down grade, the time for the renewing of
their youth has more than come. How, it may be asked,
can the needful rejuvenescence be accomplished? Careful
selection and careful rearing, on the lines suggested by
Sir Walter Gilbey, may do much to arrest further de-
generation ; but to secure a new lease of life—real reju-
venescence—there are, I believe, only two possible modes
of procedure. The one is the introduction of new blood,
the other is to induce reversion without introducing new
blood. As already mentioned, Millais, when he wished
to rejuvenate his bassets, went straight to the original
source of the breed, i. e. he crossed his bassets with

* © Race-horses,’ Sir Walter Gilbey, 1898, p. 6.
+ Quoted from the Times of December 27th, 1897, by Sir Walter
Gilbey, ‘ Race-horses,’ p. 6.

lvi GENERAL INTRODUCTION.

bloodhounds. If Millais’s example—which seems to have
produced the desired result—were followed, a number of
new unrelated Barb and Arab sires, or rather Barb and
Arab mares, would be imported, and put to our best
English thoroughbreds. But breeders hesitate in making
a fresh start of this kind, for the simple and obvious
reason that the English race-horse is not only larger
than modern Arabs and Barbs, but also fleeter. Were a
number of three or four mile races substituted for some
of the shorter ones so much in vogue, the introduction of
new blood would become imperative, with the result,
doubtless, that ere long there would be rejuvenated
horses as large and as fleet as the present thoroughbred ;
and, in addition, able to gallop as far, and maintain their
place as long on the turf, as the giants of bygone days.
Failing the introduction of new blood, of say a number of
the best mares the desert of Arabia can produce, there is
but the alternative of crossing thoroughbreds which have
been living under as different conditions as possible, the
object being to take advantage of the great good that
often results from a complete change of the surroundings
or environment.

Changes affect all the systems, but most of all the re-
productive system: they in some cases arrest degenera-
tion ; they may even lead to a kind of rejuvenescence.

In carrying out this limited form of intercrossing, two
plans might be followed. In the first place, carefully
selected American or Australian thoroughbred mares
might be put to equally carefully selected English bred
horses having the same form and general characteristics.
By this plan the risk of reversion would be reduced to a
minimum. In the next place, mares or horses from over
the sea might be mated with English thoroughbreds of a
distinctly different type, with the view of inducing, or at
least courting, reversion. Both plans might give good
results, but the second would probably be most effective,
more especially if there was reversion to a famous pre-
potent ancestor, a famous “sport” either in the line of
the sire or dam. It would, of course, be necessary to re-

GENERAL INTRODUCTION. lvii

member that the offspring would tend to take most after
the prepotent parent ; in many cases the cross-bred stock
would, from the first, resemble English thoroughbreds in
appearance, though differing from them considerably in
constitution. In selecting American or Australian sires
or dams, regard should be had to their form and record,
and, other things being equal, horses should be selected
that are free from blood recently introduced from the
mother country, 7. e. the purest available descendants of
the first good race-horses imported (into the States or
Australia) should be preferred.

Perhaps the best way to maintain the staying power
and constitution as well as the speed of the English race-
horse would be to have recourse now and again to Australia
or New Zealand for sires and dams equal, if possible, in
fleetness and size to our own thoroughbreds, but differing
from them in having a recent dash of Arab blood in their
veins.

Having discussed at some length prepotency and in-
breeding, various problems may now be considered with
which these subjects are more or less intimately in-
volved.

Breeders, to their credit be it said, like biologists, are
more or less guided by certain working hypotheses. It
is not their blame if some of the tenets making up their
creed are found wanting when put to the experimental
test, or that some of the explanations of out-of-the-way
phenomena are far-fetched or tinged with medixvalism.
The creed of the biologist is ever changing, and, except
in the case of mere hodmen, speculation and theory
are ever in advance of the facts. But with the breeder,
perhaps more than the biologist, superstitions are likely
to flourish, for it is beyond the province of the average
breeder to test his beliefs by systematic experiments.
There is not yet a Newmarket confession to which breeders
of thoroughbreds are expected to subscribe, yet there are
many beliefs or dogmas which are firmly adhered to by
the Aberdeen Angus, Galloway, and shorthorn men, as

e

|vill GENERAL INTRODUCTION,

well as by fanciers and breeders of horses, and each breed
may be said to have its own prophets.

Before, however, referring to a few of the articles that
hold a conspicuous place in the breeder’s creed, it may be
well to ask the following question, viz.: Is the wild
parent prepotent over the domestic? That the wild
parent impresses his or her characters on the offspring
more than the tame or domestic parent is the almost
universal belief.

The following experiments bear on this question :—Six
white rabbit does (all of which had produced pure white
young to white bucks) were crossed with wild brown bucks.
The forty-two half-bred offspring were at birth of a
bluish-black colour (not flesh-coloured, as is the case with
young white rabbits), and they soon developed a complete
coat of brown hair. Now that the survivors are half-
grown it is almost impossible to distinguish them from
a full-blooded wild rabbit ving in the same enclosure.
The half-breeds are, however, not nearly so shy as the
wild one, and when carefully examined they are seen to
be shghtly hghter in colour. Several have, as in many
leverets and young wild rabbits, a few white hairs along the
centre of the brow, while one has white tips to the toes of
the left fore-foot. In this case the wild parent evidently
prevails.

It remains to be seen whether similar results will
follow when inbred does of various colours are used, and
when wild does are crossed with tame bucks. It is said
the white rat, when crossed with the brown, sometimes
throws black rats. If this is the case the explanation
may be that the white rat is an albino variety of the once
common black rat. Tame albino rabbits have doubtless
sprung from several breeds variously coloured. I thought
some of my half-bred young would revert towards their
coloured ancestors, but this, as we have seen, was not the
case.

Similar results have been obtained by crossing the
ordinary turtle-dove with the white Java variety. The
offspring of a male turtle-dove and a white Java hen

GENERAL INTRODUCTION. lix

frequently, if not invariably, resemble the ordinary
turtle-dove. When, however, a male white Java dove
is crossed with an ordinary turtle-dove hen, a white bird
is occasionally obtained. Intermediate forms never
seem to occur; at the most the faintest yellow tinge is
at times visible, chiefly at the tips of the wings. The
cross-bred birds are very fertile inter se, and when the
offspring of a white Java cock they yield about an equal
number of white and turtle-coloured birds. Even when
a cross-bred dark bird was mated with a pure-bred white
Java bird the result was an ordinary turtle-dove,—not, as
might have been expected, a white bird. With the
turtle-doves as with the rabbits, the older type is pre-
potent. Experiments with closely inbred white birds
might give somewhat different results.*

As already mentioned, a duck, the offspring of a
black Cayuga drake and a common wild duck, produced
to a wild drake seventeen young. Of these, seven take
after the wild sire, the others after the black Cayuga
grandsire. In this case the influence of the wild sire is
not as marked as might have been expected. With the
help of reversion they might very well all have assumed
the dress of the common wild duck,

Hybrids between the wild pheasant and various breeds
of fowls are common. Several I have examined were
more like fowls than pheasants; on the other hand, a
cross between a bantam cock and a grouse is described
by Millais as generally more resembling a grouse than a
bantam.

Of the nine zebra-horse hybrids I have bred, only two
in their make and disposition take decidedly after the
wild parent. As fully explained below, all the hybrids
differ profoundly in the plan of their markings from the
zebra, while in their ground colour they take after their
respective dams or the ancestors of their dams far more
than after the zebra,—the hybrid out of the yellow and

* The experiments with turtle-doves were made by Mrs. Cospatrick
Dunbar, partly in London and partly at Earnbank, Bridge of Earn,
Perthshire.

lx GENERAL INTRODUCTION.

white Iceland pony, e.g., instead of being light in colour,
as I anticipated, is for the most part of a dark dun colour,
with but indistinct stripes. The hoofs, mane, and tail of
the hybrids are at the most intermediate, but this is perhaps
partly owing to reversion towards the ancestors of their
respective dams. In their disposition and habits they
all undoubtedly agree more with the wild sire. How
could it be otherwise? However hard the life of many
of our horses may be, they know little of the real
strugele for existence which counts for so much amongst
their wild relatives. If they lack intelligence, and
readily submit their backs to the burden, they are all
the more thought of. In the wild state the wits are
kept sharpened, and the life-saving instincts maintained
at a high standard. It is doubtless for this reason the
hybrids in their mental equipments are more zebras than
horses ; in the one case the instincts have been kept at a
high state of efficiency, in the other they have been
neglected. Nevertheless the wild parent is not invariably
all-powerful in moulding the character of the hybrids.
This is well illustrated by the three zebra-hybrids bred
some years ago by Lady Meux at Theobald’s Park,
Hertfordshire. These hybrids are by different sires, but
all out of the same zebra mare. The oldest of the three,
by an English pony, is of a yellowish-brown colour, and
but faintly striped. With the exception of the lees, the
hog mane, and mulish tail, this hybrid in make is very
like a small stoutly built cob. Moreover it is very
docile and unexcitable. The second eldest is brilliantly
and richly decorated with brown stripes over a bright
bay background. ‘The sire in this case was, it is said,
an American pony. Again, there are zebra legs, a
somewhat stout body, a plain head, and a short neck,
but in disposition this hybrid is a zebra. The third
hybrid is only very faimtly and partially striped, and in
most respects it takes after the sire, a small wall-eyed,
light bay Highland or Shetland pony.

To mention yet another case. A zebra-donkey hybrid
out of a zebra mare is, in many respects, far more an ass

GENERAL INTRODUCTION. lxi

than a zebra. In this hybrid, which was bred in France,
the dorsal, shoulder, and leg stripes have evidently been
inherited through the donkey sire, while the head, ears,
mane, and legs have as evidently the stamp of the zebra.
In disposition this hybrid is far more a donkey than a
zebra—no mule was ever half as stubborn. Perhaps the
wild parent counts for but little in this case, because of
the donkey sire having been inbred. A similar hybrid,
bred in the Melbourne Zoological Gardens, though darker
and less distinctly striped, is as much a donkey in its
habits and instincts. It thus appears that the wild
parent is not necessarily most powerful in impressing
even its mental peculiarities on the offspring. This is a
matter of some practical importance. It implies, e.9.,
that by careful selection cross-breeders will be able to
produce, within certain limits, offspring differing greatly
from each other, both mentally and physically. I say
cross-breeders, and not bybridisers, because the difference
between species and varieties is often more a difference
of degree than of kind. From what has just been stated,
there appears to be Jess difference in many ways between
the zebra and the horse than between the ass and the
horse, and there is about as much difference between
some of the more ancient breeds of cattle and some of
the newer breeds as there is between a bison (buffalo)
and a shorthorn. It follows that by taking advantage
of the facts already established zebra mules could be
bred either closely resembling zebras or horses. By
carefully selecting mares, or breeding mares for the pur-
pose, the objectionable zebra traits might be all but
eliminated without sacrificing any of the advantages such
a cross may bring.

The wild parent is said to be especially prepotent be-
cause it belongs to an older and longer established type
than our domestic breeds. This is very much the same
thing as saying the wild parent is well-bred, or, for that
matter, inbred ; that prepotency amongst wild animals is,
under ordinary circumstances, due to inbreeding.

Further observations will probably show that though

lxii GENERAL INTRODUCTION.

the oldest type is likely to prevail, the offspring will
take after the most inbred parent, regardless of the
length of the pedigree ; but when one of the parents Is a
sport, it is likely to transmit to at least some of its off-
spring its own peculiar characters, even if the other
parent is inbred and wild.

That sports are prepotent is supported by the results
of recent experiments with insects. Dr. Standfuss, of
Ziivich, v.g., has, as the result of careful observation and
experiment, come to the conclusion that when the normal
form is crossed with a sport or aberrant variation, the
result in many cases is that the offspring either take
after the normal form or the sport, intermediate forms
being absent.*

Having considered the question, Is the wild parent
most prepotent ? it may now be asked, Is the male pre-
potent over the female? This second question naturally
leads to the consideration of various dogmas commonly
subscribed to by breeders. It is, e. g., generally supposed
that certain structures and organs are more often inherited
from one parent than another. According to the teach-
ing of the late Mr. James Howard, (1) the male
parent is mainly responsible for the external structure,
configuration, outward characteristics, and the locomotive
system ; (2) the female parent supplies the internal struc-
ture, the vital organs, and in a larger proportion than
the male, the constitution, temper, and habits; (3) the
purer the race of the parent the more certainty there is
of its transmitting its qualities to the offspring—the
parent of the purest descent having the greatest influ-
ence ; and (4) apart from certain disturbing influences, the
male, if of pure descent and descended from a stock of
uniform colour, stamps his colour on his offspring.t

Even although these dogmas are widely accepted, they
might have been neglected in the meantime had Sir

* See paper on “ Experiments in Hybridisation,” by Mr. Dixey, M.A.,
of Wadham College, Oxford (Sedence Progress, April, 1898.)

f See Millais’s ‘Two Problems of Reproduction,’ ‘Our Dogs’ Publishing
Company, Manchester, p. 4.

GENERAL INTRODUCTION. lxili

Everett Millais not only indicated he agreed with them,
but in addition endeavoured to show that they were sup-
ported by the teaching of embryology. I must confess I
fail to find any evidence from embryology that, as Millais
puts it, “the sire influences what we can see, the colour
and anatomy ; and the female what we cannot see, 7. e. the
internal organs.” Huxley, twenty years ago, said, “It is
conceivable, and indeed probable, that every part of the
adult contains molecules derived both from the male and
the female parent, and that, regarded as a mass of mole-
cules, the entire organism may be compared to a web of
which the warp is derived from the female, and the woof
from the male.’* The work of embryologists since
1878 may be said to have confirmed Huxley’s view. By
speaking of the male as supplying the woof and the
female the warp, it is not meant that the male plays the
more prominent and important part, but rather that the
female is especially concerned in providing the substratum
on which all the organs and tissues, whether they be ex-
ternal or internal, are gradually built.

When allowance is made for reversion, inbreeding, and
various other factors, it is extremely difficult to estimate
how far the one sex predominates over the other. As
the female germ-cell (the egg) contains relatively far
more extra-nuclear protoplasm (cytoplasm) than the male
germ-cell, it might be argued that the female parent is
more than the male concerned with the actual structure
of all the organs and tissues, while the male and female
take an equal part in providing the “ constitution, temper,
and habits.” I think, however, it is safer to say, that
whatever peculiarities of structure and temperament have
been strongly inherited will be most readily transmitted,
regardless of the sex, whether they have been recently
acquired through inbreeding or derived from quite re-
mote ancestors. Save in inbred animals, characters, even
though no longer counting in the struggle for existence,
which have come down from remote ancestors are likely
to be strongly transmitted, whether they predominate in

* “ Bvolution,” p. 296, ‘Ene. Brit.,’ 1878.

lxiv GENERAL INTRODUCTION.

the male or the female; and further, characters which
have during recent times, irrespective of sex, played an
important part in enabling the species or variety to hold
its own in the struggle for existence will also be strongly
inherited. Moreover peculiarities of the nature of sports
or the result of inbreeding will also, I think, be readily
transmitted, quite irrespective of the sex of the indi-
vidual possessing them.

It would be comparatively easy to cite instances which
seem to prove that the offspring owed their colour, form,
and distinctive attitudes and movements to the male ; but
it would be equally easy to mention cases which seem to
prove that the colour and form had been derived from
the female, while the disposition, temper, and habits had
been inherited from the male. Doubtless, in some cases,
the male isinore prepotent than the female ; but in many
cases the greater prepotency is the result of the male
being of a purer breed than the female, z.e. of his being
inbred, or because some of the characters are latent in
the female. Darwin refers to the view already dealt with,
that it is difficult to eradicate a blue tint when it once
appears in pigeons, and also to the belief that the
pouter is more prepotent than the fantail. But though
blue is usually prepotent over white in pigeons, I have
twice, as already mentioned, bred pure white fantails from
almost blue birds, and the offspring of a white fantail
cock and a blue pouter hen, though having the form and
habits of the pouter, is almost white. In the last case
the male was most powerful in the matter of colour, but
counted for little in the form. It seems to be admitted
that the male ass is more prepotent than the female when
bred with the horse,—that a mule, in fact, is more like
an ass than is a hinny, and that is certainly my ex-
perience ; but, on the other hand, the female zebra, when
bred with the horse, may prove as prepotent as the male,
if the intensity of the stripes and the form of the limbs
and hoofs are taken as the standard. The Dalmatian
dog proved more prepotent than the sable collie, but this
might have been expected from the male being, by the

GENERAL INTRODUCTION. lxv

coloration test, one of the most, if not the most highly
specialised breed of dogs in existence.

The conclusion arrived at from my experiments is, that
I would not like to trust to the prepotency in the male
making up for deficiencies in the female. From the two
Clydesdale hybrids—full sisters—differing in so marked
a manner, the one, as already explained, taking after the
mare, the other after the zebra, and from members of the
same family varying greatly, both mentally and physically,
it seems to me breeders need not build much on the
supposed prepotency of the male beyond what he has
acquired through inbreeding, or by being a “sport.”
In all the offspring of my Arab Benazrek there is a
characteristic blaze. This might be to some sufficient
proof of prepotency. Buta blaze may be of the nature
of a “sport,” and if this is not the right explanation his
breeding has to be taken into consideration. He is not
only well-bred, he is highly bred ; whereas the dams of
his offspring, with the possible exception of Mulatto, are
of mixed origin, or, as we say, cross-bred. That the
internal organs are not specially derived from the female
I have very strong evidence. Hlsewhere I shall show
that a hybrid filly, out of an inbred mare and a zebra
horse, is zebra-like in some of her most distinctive in-
ternal organs. This is not, I think, because of the
influence of the wild sire, but because these organs in
the zebra are simpler than in the horse. It is doubtless
easier transmitting simple ancient structures than highly
specialised recently acquired structures.

From what has been already written it will be evident
that I generally agree with the third and fourth articles
in Mr. Howard’s creed. Other things being equal,
“the parent of the purest descent will have the greatest
influence.’ But who will undertake to say what purity
of descent means? It is not enough to know whether
any given animal has been bred on an equal or an unequal
factor system, whether one ancestor predominates or
several are about equally represented. Allowance has
to be made on the one hand for variation, on the other

lxvi GENERAL INTRODUCTION.

for reversion. Still, as a rule, the parent that has been
longest continuously inbred to one animal is likely to be
most prepotent. One might even go further than Mr.
Howard as to the transmission of colour. The general
ground colour in summer of zebras is not, as a rule,
white. Matopo, the sire of my hybrids, is a light dun,
but not nearly so ight as many cream-coloured horses,
the spaces between the stripes over the sides and back
being of a light sand or cement colour. His less remote
ancestors were doubtless still darker. In their body
colour none of my hybrids take after the sire ;* five take
after their respective dams, four are duns, and probably
take after their maternal ancestors. In their colour the
zebras, with the exception of the quagga, are highly
specialised. The majority of the quaggas seem to have
been of a yellowish-brown colour overlaid with not very
well defined stripes of a darker shade. In the Burchell
and other living zebras the stripes have evidently been
gradually intensified, and the ground colour hghtened.
Matopo has neither been able to stamp his own peculiar
pattern or his own colours on his hybrid offspring. Like
the Dalmatian, he seems to have bestowed the ancestral
markings, but (unlike the Dalmatian) he has had less in-
fluence in settling the ground colonr—this has been
determined by the dams of the hybrids. The hybrids of
the better bred mares are of a bay or chestnut hue—the
prevailing colour of Arab foals ; the hybrids of the High-
land, Shetland, and Iceland mares are of a dun colour,
and thus they probably take after the horses that in olden
times inhabited the north temperate regions. Over 90
per cent. of the horses bred in England are, as foals,
still darker than Matopo—are bays, chestnuts, or browns ;
and if inquiries were made it would probably be found foals
are still darker the nearer we approach the Arctic circle.

Of twenty Arab foals bred this year (1898) by Mr.
Wilfrid Blunt, 65 per cent. are bays, 15 per cent. chest-

* The light body colour in zebras has doubtless been acquired compara-
tively recently, hence it is never transmitted to cross-bred offspring.

GENERAL INTRODUCTION. lxvii

nut, 10 per cent. brown, and 10 per cent. grey, after the
first coat was shed.

From the Crabbet records for the last two years it
seems evident that the colour of the offspring is not
necessarily determined by the sire. If one of the parents
is bay the foal is likely to be bay. The bay mares (six-
teen in number) had, with one exception, bay foals,
although the sire in each case was chestnut: the excep-
tion was chestnut like the sire. In three cases—with a
bay sire and a chestnut mare—the foals were bay, but in
one case a bay sire and a brown mare produced a brown
foal, while in another a bay sire and a grey mare pro-
duced a foal that became grey as the first coat was shed.
It looks as if the dam had more influence than the sire,
but it is really a matter of colour and inbreeding more
than of sex. If one of the parents is white or grey, the
other chestnut or bay, the foal is likely to be either bay
or chestnut; but if the light parent is inbred the foal
may (after the first coat is shed) be grey, just as it may
be black if one of the parents is black and inbred. That
the colour of the parent may be stamped on the offspring
even when not uniform my skewbald mare has clearly
proved. In this case a uniformly coloured well-bred
bay Shetland pony failed to prevent the yellow and white
skewbald stamping her own unequally shaped blotches
on her offspring. In Norway, as in Scotland, a consider-
able percentage of the foals are of a dun colour, some
being from the first of a light cream-colour, others of a
dark mouse-colour, but the majority are probably of a
leather or red dun hue.

TELEGONY.

The belief in telegony is almost universal. That
breeders and fanciers have long believed in “ infection ”
is not to be wondered at; it is a convenient explanation
of many of the obscure phenomena that come under their
notice. That philosophers and literary men, social

Ixvili GENERAL INTRODUCTION.

reformers and physicians, have also adopted and tena-
ciously hold to the “infection”? hypothesis, is less
comprehensible. If one may judge from the attitude of
Mr. Herbert Spencer, and of certain members of the
Congress of Zoology which recently met at Cambridge,
and from the sayings of the literary prophet ‘‘ At the
Sign of the Ship,”* Weismann, and other biologists who
persist in their “ scepticism,’? may prepare for the worst.
Evidently, if experiments bearing on telegony fail to
prove that it occurs at least occasionally amongst mam-
mals, it will be all the worse for science and the workers
in the telegony corner of the scientific vineyard.

Since I turned my attention specially to the subject
in 1894 I have, in addition to making experiments hkely
to give telegony the best possible chance of declaring
itself, investigated a large number of alleged cases of
“infection.” The result, so far, is that the evidence in
support of undoubtec
is most unsatisfactory. In every case investigated the
supposed infection could be accounted for by the rela-
tively simple reversion hypothesis, and the same hypo-
thesis I am now satisfied is sufficient to account for what
at first appeared as evidence of telegony in my own

ce

“infection ” having ever occurred

experiments. I do not by any means say telegony is
impossible, that it never has occurred in the past, and
never will occur in the future; but I think I am justified
in saying “infection”? has never been experimentally
produced, and that the kind of ‘ infection” so widely
believed in by breeders, if not impossible, is at least
extremely improbable—as improbable as the almost
equally common belief that the colour of the offspring
may be influenced by ‘ mental impressions,” as Laban’s
sheep and cattle are said to have been influenced by the
peeled wands placed before them by his son-in-law,
Jacob.

What breeders understand by “infection” will be
best gathered from a few examples. The race-horse
Blair Athol had a very characteristic “blaze,” ie. a

* See Longman's Maguzine, October, 1898.

GENERAL INTRODUCTION. ]xix

striking white bald face. It is said that mares, after
having foals by Blair Athol, produced Blair Athol like
foals to other sires utterly unlike Blair Athol. In the
same way a fox terrier, after having pups to a Dalmatian
had, Millais tells us, spotted pups to a dog of her own
breed. From these two cases it will be evident that
breeders and fanciers believe in direct “infection.” I
think this kind of infection is extremely unlikely, if not
impossible. My sable collie’s pups to a Dalmatian have
only four or five patches of colour, such as occur in
foxhounds and pointers. According to the breeder’s
view of telegony, her next pups to a collie like herself
should, if she has been “infected,” be spotted like a
Dalmatian. This is evidently an untenable position.
Again, all my hybrids profoundly differ in the number
and plan of their stripes from their Burchell zebra sire ;
yet, according to the popular view, the subsequent foals
of their respective infected (?) dams should more or less
resemble a Burchell zebra. This is an equally untenable
position. The collie, if “ infected,” can only be expected to
produce in future pups like a foxhound or pointer; the
mares, if “‘ infected,” can only in future be expected to
produce foals more or less like zebra-hybrids. My flea-
bitten New Forest pony, after having a mule foal, has
had two foals to a grey Arab with a blaze. Next year
she is expected to have a foal to a bay hackney pony.
Should this foal have a ‘blaze,”? before ascribing it to
telegony it will be necessary to prove a blaze had not
occurred for many generations in one or other of the new
foal’s ancestors, or was not a “sport.” In the case of
the fox terrier pup, before ascribing the spots to the
previous Dalmatian sire it would be necessary to prove
that similar spots had not occurred in some of the pup’s
ancestors.

Believers in telegony, with tiresome unanimity, ever
revert to Lord Morton’s mare. The more I consider Lord
Morton’s case the less satisfied I am that the mare so
often referred to was infected by the quagga. A glance
at Figs. 14 and 15 (pp. 66 and 67) shows that the pure-

lxx GENERAL INTRODUCTION.

bred filly—every inch a horse in make—had far more
stripes than the hybrid, and that the mane is represented
as lying to one side. Darwin, in coming to the conclusion
that the mare in question had been infected, seems to
have been largely influenced by two beliefs: (1) that
stripes are uncommon in Arabs ; and (2) that the mane in
the filly was upright. But extensive inquiries have con-
vinced me that stripes are not by any means uncommon
in Arabs. Mr. Wilfrid Blunt has recently been good
enough to present me with a high-caste Arab foal, show-
ing as distinct stripes in the region of the “knee” and
hock as in Norwegian dun-coloured ponies; and, in
addition to a dorsal band, faint indications of markings
across the withers. That stripes are less common in
Arabs and their thoroughbred descendants is due, I be-
lieve, to Arabians disliking duns, which they say “are
only fit for Jews to ride.’ Were it certain the mane of
the filly was, as alleged by Sir Gore Ouseley’s groom,
always upright, the case for “ infection’? would be well-
nigh complete. But the evidence in support of an up-
right mane in the filly is far from satisfactory. The
mane, as already mentioned, is represented as lying to
one side in Agasse’s drawing. Even in the quagga
hybrid the mane was not upright, it arched to one side,
as is the case, at least during winter, in all except one
of my zebra-horse hybrids, and in Lady Meux’s three
horse-zebra hybrids.

Darwin seems to have departed somewhat from his
original opinion about “infection.” At least some
years before his death he had come to the conclusion
that telegony only rarely occurred, that it was a “very
occasional phenomenon.” If in the general form—the
inaue, tail, hoofs, aud temperament—the subsequent foals
of Lord Morton’s mare were horses, and not at all like
the quagga hybrid, the stripes are the only evidence in
favour of infection. The stripes, however, if Agasse’s
drawings may be trusted, are the stripes of a horse rather
than the stripes of a zebra or a quagga, or a quagea,
hybrid, 7. e. they seem to have been inherited from the

GENERAL INTRODUCTION. )xxi

ancestors of Lord Morton’s chestnut mare, or through
the black horse with which she was subsequently mated.
To make the experiment complete, she should have been
mated with a horse that was not in the habit of having
striped offspring, instead of with a black Arab (in which
stripes were probably latent), or at least as well as with
the black Arab. But even if it be admitted Lord Mor-
ton’s mare was infected by the quagga, a comparison of
the filly (Fig. 15) with the first sire (the quagga, Fig. 18)
conclusively shows the infection was not of the kind
believed in by breeders; it did not result in quagga-
like any more than it resulted in quagga-hybrid-like
markings. At the most the quagga produced some dis-
turbance, which caused the mare to throw back to her
own ancestors.*

Breeders dread “ infection’? because they believe the
subsequent offspring take after the first sire; that a
thoroughbred mare may throw back to a cart-horse,
while a mare which has bred mules is likely to throw
back to a jackass. If the sire (supposing he has any
influence on the subsequent progeny by other sires) leads
to their resembling some former ancestor of their dam,
breeders of thoroughbreds should in most cases endeavour
to have their mares infected. If by putting their
mares to donkeys the subsequent pure-bred foals
“‘harked back ” to ancestors some generations removed,
the sooner this plan is adopted the better. Reversion
to the vigorous hardy horses of bygone days would be
the salvation of the English race-horse.

Though my experiments are not yet at an end, they
have proved conclusively enough that ‘infection ” does
not always occur, as many seem to think. They, in fact,
support the view of experienced Continental mule breeders,
which is that telegony, if it occurs at all, occurs but
seldom. Should it eventually be found that out of say

* Tt is conceivable that the previous sire, though not responsible for
visible structural changes in the subsequent offspring to other sires, may
profoundly influence the constitution, ¢. ¢. lead to physiological “ infection.”
He might, e.., confer immunity to certain diseases.

Ixxil GENERAL INTRODUCTION.

fifty pure-bred foals, the offspring of mares that had been
previously mated with my zebra stallion, there is not a
single instance of “infection,” the telegony dogma will
be so discredited that it may in future be neglected by
horse breeders ; and if similar results follow experiments
with dogs, rabbits, and other animals, the hypothesis
ought ere long to be regarded ag a mere superstition, and
finally take its place with the barnacle tree and other
legends of a credulous past.

In the last of the three papers, Mulatto’s second
foal is described at some length. Since the description
was written I have seen faint stripes on the croup of two
pure-bred foals. I have also seen stripes more distinct
than the bands on black cats over the shoulders and sides
of an old very dark mouse-dun Highland cob, and frag-
ments of as many stripes as occurred in the quagga in a
leather-dun Norwegian pony. These striped foals and
horses, taken along with the foal bred by Darwin, which
had a striped face as well as stripes across the croup,
point to the conclusion that all the stripes on Mulatto’s
second foal may very well have been due to simple re-
version. If next spring Mulatto, as is hoped, has a
foal to a pony of her own peculiar strain, further light
may be shed on this interesting but obscure problem.

Three of the four mares that in 1897 had hybrids, have
each during 1898 had a foal to a horse sire ; the fourth
mare has again a hybrid by Matopo. It will be well to
refer to these foals separately.

(a) Tundra’s Subsequent Foal.—Tundra, the yellow and
white (skewbald) Iceland pony, has had in all three
foals. Her first, sired by an Iceland pony, was a bay ;
her second is the zebra-hybrid Heckla, born May 22nd,
1897 ; her third (born June 15th, 1898) is a skewhald, the
sire being a bay Shetland pony. Heckla, as already
pointed out, is very dark in colour, indistinetly striped,
and in make and action lke a well-bred pony. Neither
in colour, make, nor disposition does the last foal show
the faintest resemblance to the previous zebra sire, nor
yet to her half-sister Heckla. As already mentioned, the

GENERAL INTRODUCTION. lxxili

new foal is ridiculously like her dam ; the yellowish-brown
patches occupy the same positions, and are of nearly the
same shape and relatively of the same size,—even the mane,
forelock, and tail agree in their colouring. In make and
in gait, as well as in colour, the foal is her mother’s own
daughter,—the bay Shetland sire has apparently counted
for nothing. It may be said that for two reasons evidence
of “infection,’’ even if there is such a thing, could not
be looked for in the subsequent foals of the Iceland pony.
In the first place she had a foal before she was put to the
zebra, and in the next place she is evidently prepotent.
If only the first sire is capable of “infecting,” then the
Iceland pony is not a suitable subject for such an experi-
ment, but believers in telegony are not all at one on this
point ; in many of the alleged cases of telegony the infec-
tion is said to have been caused by the second or third
mate. There can be little doubt that Tundra is inbred,
at least as contrasted with many other ponies. Judging
by her first foal being bay, she would not be considered
inbred in Iceland, but in all probability the Iceland ponies
are, on an average, more inbred than ordinary Shetland
or Highland ponies. They have been long isolated on a
small remote island, into which comparatively little new
blood has, as far as I can learn, been recently introduced.
On the other hand, had Tundra’s last foal given distinct
signs of infection, it would have afforded very strong
evidence indeed in favour of telegony. But I may
explain I selected Tundra not only to apply a severe test,
but also because I wished to experiment with a mare
which had already produced unstriped offspring, and
because I was anxious to see whether a mare more than
two thirds white would throw a lighter coloured hybrid
than a black or bay mare. As already stated, the hght
colour of the mare counted for just ns little as the light
colour of the zebra ; the hybrid is extremely dark, partly,
doubtless, because the dam has descended from dark
mouse-coloured ancestors, and partly because zebras are
unable to transmit to hybrids their recently acquired light
ground colour.
lp

lxxiv GENERAL INTRODUCTION.

(b) Nora’s Subsequent Foal.—Nora, as explained below,
is an almost black 11:1 hands Shetland pony. Like
Tundra, she had a foal before she was put to the zebra,
but, unlike Tundra, she is not prepotent ; instead of being
a “repeater” she tends to produce offspring lke the re-
spective sires with which she is mated. Her first foal,
as explained in the telegony paper, was at birth of a bay
colour, and marked with a dorsal band, with bars across
the legs, and a number of stripes across the withers,—was,
in fact, for a time nearly as richly banded as the filly
bred from Lord Morton’s mare. Though a number of
these stripes vanished with the foal’s coat, three distinct
bands persisted, as in Lord Morton’s quagga hybrid,
across the withers. In Nora I had evidently a mare
with a tendency to produce striped offspring, but whether
the first foal inherited the stripes from his dam or from
his sire it was at the outset impossible to say, both
parents being equally dark in colour, and, though not
related, of the same strain. Nora’s hybrid foal (Norette)
is more of a zebra than any of my other hybrids. The
body colour is, as a whole, of a leather dun shade, but in
some parts it is reddish brown, the stripes are nearly
black ; and, instead of spots, there have been from the
first numerous well-marked stripes across the loins and
croup* as in the Somali zebra, and, as in Romulus,
numerous rounded arches on the brow. The hoofs are
longer than in the zebra sire, and the mane, though long
and pendent in winter, is in summer short and quite up-
right. While it might be difficult for Matopo to infect
the inbred skewbald Iceland pony, he had evidently an
excellent opportunity of permanently stamping his cha-
racters (or those of his ancestors) on the black four-year-
old Shetland pony.

Nora, having given birth to her hybrid, was put to a
small Welsh pony, a bay with black points and black
mane and tail. The Welsh pony being of a different
breed, and having some dark hairs in the vicinity of the

* From the markings over the croup of the hybrids a fairly accurate
estimate may be formed of the prepotency of their respective dams.

GENERAL INTRODUCTION. lxxv

withers and over the croup, I at least expected Nora’s
third foal to have as many stripes as her first. Nora’s
third foal, however, now that it is five months old, as
closely resembles the sire as the Iceland’s third foal re.
sembles her prepotent skewbald dam—another proof that
Nora, unlike Tundra, is not inbred. The resemblance is
not only in colour, but also in make and action ; and, as
far as one can judge, also in temperament. As in the
skewbald foal, there is not yet any indication whatever,
either of the previous sire, or the previous hybrid foal
Heckla. Even the shoulder and other stripes present in
Nora’s first foal to the Shetland pony are absent. The
third foal is hence less zebra-like than the first, notwith-
standing the fact that the sire of the intermediate foal
was a zebra far more richly decorated with stripes than
Lord Morton’s quagga. But though there are no stripes
visible at the fifth month, there were faint indications of
stripes over the croup and hind quarters at birth ; while
over the brow the hair, though not coloured, was so ar-
ranged that in certain lights it seemed to form a series
of arches. As the first coat was shed all the indications
of stripes disappeared, and I anticipate that when the
winter coat is shed next spring Nora’s third foal will, in
her coloration, be almost identical with her sire, the bay
Welsh pony.

It thus appears that in Nora we have a non-prepotent
mare that tends to reproduce, not her own characters, but
those of the sire with which she is mated ; and yet, though
extremely sensitive, there is no indication from her last
foal that she had been previously mated with a zebra.

(c) Biddy’s Second Foal.—Biddy, I may repeat, is a
three parts bred bay Irish mare, with black points. In
her colour she is more typical, i.e. she more closely
approaches the dun-coloured ancestors from which horses
seem to have sprung than is the case with either the
skewbald Iceland or the almost black Shetland pony.
Further, she is neither prepotent like the Iceland, nor
yet particularly non-prepotent like the Shetland.

Biddy is of about the same age, and has from the

lxxvi GENERAL INTRODUCTION.

first been quite as vigorous and healthy as the zebra
stallion Matopo.

In the hybrid Remus, Biddy’s first foal, the stripes are
dark brown, the body colour a rich somewhat light bay.
Although well striped he takes after the dam about as
much as after the sire, and hence is a striking contrast to
Lord Morton’s feebly marked quagga hybrid. In every
respect I consider the bay Irish mare an excellent subject
for testing the telezony hypothesis.

Biddy’s second foal is by a thoroughbred chestnut
horse (Tupgill) with a frontal star. As generally happens
when bays and chestnuts are crossed, the foal is bay in
colour. As in the dam, there are black points, and, lke
the sire, a star on the forehead. At birth the second
foal was 354 inches at the withers; Remus was an inch
smaller—at five months 48 inches, against 44% for Remus,
At five months the mane was lying to both sides, in
Remus the mane has from the first been upright. In the
ears, tail, chestnuts, hoofs, and in every other respect, the
second foal, at the age of six months, agreed with pure-
bred foals, 7. e. it in no way suggested either a zebra or a
zebra hybrid. But during the first three months there
were indications of stripes in the region of the withers,
on the sides, and across the croup and hind quarters.
These indications were mainly produced by a wavy condi-
tion of the hair, but in some lights several of the bands
across the croup seemed to differ slightly in colour from
the intermediate spaces. During the fourth month all
the indications of stripes practically disappeared, and I
anticipate that when the winter coat is shed next spring
the second foal will be quite devoid of stripes and all
other suggestions of zebras or zebra hybrids.

I may here repeat that, during the present year, I
have seen similar indications of stripes over the croup of
quite a number of foals. ‘To begin with, in highly bred
foals with very fine coats there are often at birth across
the sides and croup, and especially in the vicinity of the
flank feather, narrow markings that might be mistaken
for stripes. These markings, as explained in the third

GENERAL INTRODUCTION. |xxvii

paper, are caused by the hair being arranged in well-
marked tracks or ridges, separated by almost hairless
spaces. In these tracks, which were very distinct at
birth in a cinnamon-coloured foal I bred this year, out of
a bay half-Arab mare—the sire was a chestnut thorough-
bred horse—we have, it may be, a restoration for a time
of an ancestral condition. Sometimes, along with these
hair-tracks or ridges, there are faint stripes seen only in
certain lights, but evidently in part due to subtle colour-
ing. Stripes of this nature I noticed plentifully scattered
over a reddish-grey foal out of my flea-bitten New Forest
pony by the grey Arab, Benazrek. More common and
more evident are comparatively broad wavy bands, often
seen across the croup and on the brow of half-bred bay
foals. These bands may occupy the position of ancestral
stripes—stripes out of which the colour has been com-
pletely washed since they ceased to count in the struggle
for existence. My reason for supposing they represent
ancestral stripes is based on the fact that they occupy
the position of stripes in a yellow-dun Norwegian pony,
and of the stripes over the croup of one of Lady Meux’s
hybrids, which may have been inherited either from the
American trotting horse or from a remote common an-
cestor. I am now satisfied that foals are far more often
marked with stripes—apparent or real—than is generally
supposed, and that stripes will be often seen in horses if
they are carefully looked for. From this it follows that
the stripes on the “colts”? bred by Sir Gore Ouseley
out of Lord Morton’s mare by the black Arab horse are,
after all, not so very remarkable. The zebra, Matopo,
having failed to “ infect ” four mares, it is quite evident
that telegony does not invariably occur, as many breeders
believe. It remains to be seen whether it occurs in even
1 or 2 per cent. of cases, as was supposed by Romanes.
I have now eight mares that, if telegony is true, may
have been infected. I hope to continue breeding from
these mares and from their offspring for some years to
come, in order to give the supposed infection an oppor-
tunity of showing itself. If, out of fifty or a hundred of

lxxvill GENERAL INTRODUCTION.

the descendants of these mares, a single case of undoubted
infection is obtained, the fact of telegony will be estab-
lished ; if, on the other hand, not one out of a hundred
foals “harks back ” “infection,” if it occurs at all, may
be treated as a negligible quantity.

In addition to the experiments with mares, I have been
on the outlook for evidence in favour of telegony m
rabbits and dogs, fowls and pigeons. I first made sure
that six white rabbit does produced white young to white
bucks. The white does were then crossed with wild
bucks, with the result, as already stated, that they brought
forth over forty young that could with difficulty be dis-
tinguished from wild rabbits. When next bred with a
white buck, they all produced perfectly white young,
proving, as far as colour could show, that none of the
does had been infected. I propose making further ex-
periments with rabbits next summer.

The results obtained with fowls and pigeons also failed
to give any support to the telegony hypothesis. The
experiments with dogs already completed, have not sup-
ported the deep-rooted and wide-spread belief that, in
dogs, at least one of the subsequent offspring almost
invariably takes after the first (or previous) sire if it
happens to bea mongrel, or to belong toa different breed
from that of the dam.

SATURATION.

Almost identical with telegony is the saturation hypo-
thesis. Bruce Lowe, the prophet, if not the originator
of the saturation theory, defines it as follows :—“ Briefly
put, it means that with each mating and bearing the dam
absorbs some of the nature or actual circulation of the
yet unborn foal, until she eventually becomes saturated
with the sire’s nature or blood, as the case may be.’’*
That something of this kind occurs in the human family
is also widely believed. Bruce Lowe, I understand,

* Bruce Lowe, ‘ Breeding on the Figure System,’

GENERAL INTRODUCTION. Ixx1x

meant to account for telegony by the saturation theory,
but evidently the saturation theory goes further than
telegony ; it seems to imply an actual change in the
organs and tissues of the dam,—she is said to be
“saturated with the sire’s nature or blood ;”? whereas,
according to Weismann, Romanes, and others, telegony,
if it occurs, only influences the germ-cells, which stand
im much the same relation to the parent that a cargo of
wheat does to the ship conveying it. Evidence of
saturation is looked for, not so much in a change in the
appearance of the female parent, though a change of
this kind is sometimes insisted on, as in the offspring.
They are said to become progressively more and more
like the sire, the second foal taking more after the sire
than the first, the third than the second, and so on.
Now, as it happens, a paper was read at the recent
Zoological Congress at Cambridge by Professor Hubrecht
of Utrecht, which seems to lend support to this theory
as well as to the telegony theory. The object of this
paper was to show that blood-corpuscles in some mammals
pass bodily from the foetus into the tissues of the dam.
It is not asserted that this happens in the mare; on the
contrary, the inference is that in the horse, pig, and
certain other families this passage of the foetal blood-
corpuscles does not occur. But even if it be admitted
that the “actual circulation’’ or blood of the unborn
foal is absorbed, it does not necessarily follow that the
nature of the dam is in any case gradually altered,
except in as far as the foetal corpuscles are the bearers
of the germs of disease. The saturation theory may
also be said to be supported by the recent investigations
of M. Charrin, who found that ‘‘diphtheritic toxins
injected into the embryos of a pregnant rabbit caused
the death of the mother on the fifth day ;” * and further,
that a rabbit could be rendered immune by injecting
protective toxins into the embryos. M. Charrin inters
from his experiments that the characteristics acquired by
the mother from one set of embryos could be handed on
* The Medical Press, October 5th, 1898, p. 360.

Ixxx GENERAL INTRODUCTION.

to other embryos by a different sire. But even should
further experiments justify this conclusion, it does not
follow that there is either telegony or saturation.”

I have been led to refer to saturation because the
second hybrid of the Clydesdale mare is more a zebra
than her first. Some seem to think the Clydesdale has
already been “saturated” by the zebra. It is a matter
of common knowledge that the members of any given
family, litter, or brood by the same parents vary con-
siderably in coloration, form, and disposition. That the
second Clydesdale hybrid differs from the first is hence
not a unique, nor yet an unexpected phenomenon. But
though the members of the same family often differ from
each other, it by no means follows that the cause of this
variation has yet been discovered.

If the dam in form, &c., gradually assumed the cha-
racters of the sire, and if the resemblance of the offspring
to the sire proceeded at a progressive rate, there would
be a presumption in favour of saturation. But un-
doubtedly this is not invariably the case, and when it
does happen that the female appears to assume the cha-
racters of her mate, or the offspring to become more and
more like their sire, a simpler, or at least a more scientific
explanation will doubtless be available. In large families
the youngest children often take more after the mother
than the eldest. Of Lady Meux’s three hybrids out of
the same zebra mare, the youngest is undoubtedly most
like a horse, but the intermediate one is by a long way
most like a zebra. The Clydesdale’s second hybrid is far
more a zebra than her first, not in colour, but in make
and gait and disposition. If the striking difference be-
tween the two full sisters is not due to saturation, how
can it be explained? A possible explanation will be
easier if we consider for a moment some of the results of
cross-fertilisation, It is almost inconceivable that two
germ-cells derived from two separate animals or plants
can ever be identical either in form or structure. Hence,

* Experiments with toxins might prove that physiological ‘ infection ”
occurs.

GENERAL INTRODUCTION. lxxxi

when two germ-cells—one the representative of a male,
the other of a female animal or plant, more faithful re-
presentatives than any two members of Parliament can
ever hope to be of their respective constituents,—when
these somewhat differently constituted germ-cells meet
and completely fuse, the new cell formed will (except
under special and unusual circumstances) differ not only
from each of the two original cells, but probably also
from every cell that has ever previously existed or will
exist. If anattempt were made to sort the members of
two large electoral districts, it would be found impossible
to divide them into couples that in every respect agreed
with each other; the difference would of course be
eveater if the females of one side were ranged with the
males of the other. Differences in form and colour
would be at once evident, but the differences in tempera-
ment might be even greater. If the districts happened
to be far apart (one in, say, the south of Ireland, the
other in the north) all the differences would probably be
accentuated. The units of protoplasm making up the
essential parts (the chromosomes) of two germ-cells
doubtless often differ quite as much as the members of
two constituencies—differ in form as well as in affinities.
To make the comparison at all complete between two
germ-cells and the electors of two districts, it would be
necessary to include not only the women and children,
but also the less remote ancestors, and at least the ghosts
of the remote ancestors. If in such a collection only
those who could find mates the image of themselves in
structure and temperament were allowed to live, long
would be the list of the doomed. Among the survivors
the less remote ancestors would be well represented,
while amongst the doomed the representatives of quite
recent generations would be extremely abundant. The
reason of this being that in bygone times our islands
were inhabited by perhaps a single nearly uniform race,
whereas, during recent centuries, wave after wave of new
types has reached our shores, great waves of Celts,
Romans, Angles, and Norse, and smaller waves of Slavs,

Ixxxii GENERAL INTRODUCTION.

&c. In the same way, if only the units of the two germ-
cells which agree in structure and have a certain affinity
for each other are capable of forming stable combina-
tions, there must often be millions of units that fail to
enter into the composition of the new cell.

According to Mr, Galton’s law, the immediate parents,
on an average, only actually provide half of the units
composing the new cell, the other half being provided
indirectly by the ancestors. But evidently the extent to
which the immediate ancestors are represented im the new
cell (out of which the new individual is eventually formed)
will, other things being equal, depend on how much the
individuals (parents) from which the cells came essentially
agree with each other. If alike and closely related the
immediate parents might be represented by more than
half the units; if unlike and unrelated, by considerably
less than half the units in the new cell—the potential
new individual. If one parent happened to be prepotent
and the other not, only one of the parents might pre-
dominate in the new individual.

From what has been said it will be evident that quite
a number of results may follow the union of two germ-
cells. Under certain conditions a considerable departure
muy be made in one or more directions, and lead to the
appearance of something strikingly new, i.e. to the ap-
peurance of a sport. Instead of marked progress, there
may be marked retrogression towards a remote ancestor.
This when the units repel rather than attract each other,
or unite to form unstable and short-lived combinations.
As a rule, however, the result is neither a marked step
in a new direction nor a long step in a backward direc-
tion. There is often slight progress in one or more
directions, 7.e. normal or continuous variation, accom-
panied by slight regression in others.

Instances of regression we have (1) in the case of the
last Iceland foal, which is an exact reproduction of the
mother ;* (2) in the Angora rabbit, which is a restoration

* This might be either considered an example of prepotency or re-
gression to the mother’s ancestors.

GENERAL INTRODUCTION. Ixxxiil

of the grandmother; (3) in the collie-Dalmatian pups,
which are apparently a reappearance of fairly remote
ancestors ; and (4) in the fantail-owl-archangel pigeon, in
which we have an almost complete reversion to the common
ancestor of allthe pigeons. Examples of progressive and
of a combination of progressive and regressive changes
might also be given.

To return to the Clydesdale’s second hybrid. Is it
more a zebra than the first because the mare has been
saturated by her zebra mate, or can the difference be
otherwise accounted for? I think in the second hybrid
we have evidence of further reversion than in the first
to the ancestors of the dam, and at the same time more
of the characteristics of the zebra or of the ancestors of
the zebra.

The Clydesdale’s second hybrid (Black Agnes) is the
darkest of all the zebra hybrids I have bred. I have
already stated that mares have more influence in deter-
mining the ground colour than the zebra, probably because
they have not departed so far as the zebra from the
original colouring. Unfortunately I have been unable to
find out the colour of the recent ancestors of the Clydes-
dale mare; but as the white fantail pigeons resemble a
white grandparent instead of their blue parents, Black
Agnes probably takes after a grandparent having latent
stripes. This would not only account for her being a
nearly black-mouse dun, but also for the faint horse-like
stripes across the croup.

The numerous stripes proclaim the influence of the
zebra sire, but quite as suggestive of the zebra are the
make, movements, general habits, and intense vigour, in
all of which Black Agnes is a striking contrast to Brenda.
From the outset the second hybrid has been more intense
and more vigorous, and more restless when away from
her dam, than Brenda. It is conceivable that the dark
colour of Black Agnes is partly due to the fact that she
is a stronger and more vigorous foal than her full sister
Brenda, for intense energy often expresses itself in deeper
or richer coloration,

Ixxxiv GENERAL INTRODUCTION.

Taking all the facts into consideration, instead of
ascribing the difference between the first and second
Clydesdale hybrids to saturation, I am inclined to ascribe it
partly to more pronounced reversion, but mainly to better
nutrition—to a greater ripeness—of the germ-cells from
which it originated.

In the same way I account for the difference between
members of the same family, and between full brothers
and sisters of the same litter or brood. Sometimes the
difference is due to abnormal or discontinuous variation—
to some of them being sports,—-sometimes to more or less
marked reversion to the ancestors of either parent, but in
the majority of cases I believe it is mainly a question of
nutrition.* The experiments with Echinoderms + already
mentioned especially suggest this. Whether the hybrid
Echinoderms resembled the one species or the other
depended on the relative degree of ripeness of the germ-
cells. At the beginning of the season, when the germ-
cells of the one species (Species A) were unripe, the hybrids
resembled the other species (Species B) ; but as ripe germ-
cells of Species A increased, the hybrids became more and
more like A. It is equivalent to saying the prepotency of
the germ-cell, other things being equal, varies with its ripe-
ness, or, in other words, its state of nutrition. Abundant
evidence could be given to prove that there is, as a rule,
an intimate relation between the nutrition of the germ-
cells and the nutrition of the individual in which they
are stored. Just as the grains of wheat may materially
suffer from the bad state of repair of the ship in which
they are carried, so may germ-cells suffer when the body
in which they are lodged is out of condition, ill-nurtured
or over-strained. As the grains of wheat too early

* Asan instance of the influence of nutrition during development, I
may meution that I recently found that eight rabbits in one uterine horn
were exactly the same weight as four rabbits in the other horn. This
looked like a case of superfcetation, but as the eight small fcetuses were as
well developed as the four large ones, the difference was evidently due to
the same amount of nourishment being provided for each horn regardless

of the contents.
t+ Vernon, Roy. Soc. Proceed., May 26th, 1898.

GENERAL INTRODUCTION, lxxxv

harvested may produce an indifferent crop, so may imma-
ture germs produce indifferent offspring. ‘T’o summarise,
I believe experiments may show that the difference
between members of the same family, and members of the
same brood or litter, is mainly due to the structure and
condition of the germ-cells, and to the nature of the com-
binations formed when the carriers of heredity, the proto-
plasmic units derived from two separate individuals (the
parents), actually combine to form the new cell out of
which the new individual is gradually developed.

STERILITY IN EQUINE HYBRIDS.

It is not in obedience to any natural law that hybrids
are, as a rule, sterile. Formerly zoologists were ever
ready to consider intersterility as strong evidence of
specific distinction, even when the mutually sterile forms
were almost identical in structure and habits. Were
structure alone taken as the standard, not a few of the
animals that are looked upon as mere varieties would be
raised to the rank of species, while a number of species
would be degraded to the rank of varieties. Even as it
is, a number of species yield when crossed fertile off-
spring. For example, hybrids between the common goose
and the Chinese goose—two very distinct species—are
perfectly fertile, as are hybrids between the common duck
and the pintail duck, and between various species of
pheasants. The Indian buffalo and the American bison
produce fertile hybrids with the wild ox of Europe ;
while the common humped cattle of India yield fertile
hybrids with the domestic ox.

Amongst plants, hybrids are sometimes quite fertile ;
while some crosses are quite, or almost, sterile. There
is no hard and fast line between species and varieties, and
hence there can be no fundamental difference between a
hybrid and a cross, nor yet any @ priori reason why any
given hybrid should be sterile, or any given cross fertile.

It is no longer possible to contend that species were
originally endowed with mutual sterility by way of pre-

Ixxxvi GENERAL INTRODUCTION.

venting the confusion that would result from free inter-
breeding. Sterility has doubtless been acquired in some
cases slowly, in cthers abruptly, but how it has been
acquired it is impossible in most cases even to guess.
Intersterility has not hitherto been acquired by any of
our breeds of pigeons, or dogs, or horses, or cattle ; but
this may be due to their comparative youth, or to the
artificial conditions under which they were produced and
live. Romanes believed that the moment any variety
became sterile, or nearly sterile, with other varieties and
with the parent species, that same moment it mounted
the first rung of the ladder leading to specific rank. That
sterility between varieties would improve their chances of
developing into species is sufficiently evident ; but that in
the majority of cases sterility, however acquired, is the
starting-point—the password—towards specific distinction
has not been established.

Mr. Galton thinks prepotency is a highly heritable
sport. Sterility may also be a sport, an aberrant varia-
tion, not due to or associated with any demonstrable
structural changes.

It seems to me experiments might show that preferen-
tial mating accounts for much. Horses are quite re-
markable for their strong likes and dislikes, and the same
may be true of many other animals. Preferential mating
(apart from sterility) might, through inbreeding, gradu-
ally build up distinct more or less intersterile prepotent
varieties.

That intersterilty may occur without any apparent
change in the reproductive organs is extremely probable.
This is suggested by the fact that a large number of wild
animals invariably fail to breed—are virtually sterile—
in confinement. But intersterility seems to arise without
even any appreciable change in the environment, and it
is well known that a not inconsiderable number of animals,
though perfectly formed, are quite sterile; or, what is
even more suggestive, sterile with some individuals but
not with others, or sterile until the system receives some
sudden shock, or until changes are gradually produced by

GENERAL INTRODUCTION. Ixxxvil

a different kind of food. In discussing sterility, it is
generally pointed out that of all the systems the repro-
ductive system is most sensitive to changes in the sur-
roundings.

If the reproductive system is especially sensitive, if,
e.g., by inappreciable changes in the surroundings fer-
tility is increased, impaired, or completely lost, need we
be surprised that hybrids (in which the reproductive
system is of necessity modified by regressive and other
changes) are frequently sterile ?

But it will be asked, What evidence is there that the
reproductive system of hybrids in any way differs from
that of the parent species? Strange as it may seem,
there does not yet appear to exist an account of the re-
productive system of either mules or hinnies, or, as far as
I can discover, of any mammalian hybrids. Female
mules may, as is now and then alleged, be fertile, while
male mules may be invariably sterile, but until the germ-
forming glands of both male and female mules and hinnies
have been systematically investigated it is hardly safe
to hazard an opinion on the subject in the absence of
well-authenticated cases of fertility. JI have not yet had
an opportunity of examining either the germ-forming
glands of ordinary mules or hinnies, but I have recently
had the chance of learning something of the reproductive
glands of zebra hybrids.

Sterility of Male Zebra Hybrids.—In the two-year-old
hybrid, Romulus, the reproductive apparatus seems to be
fully developed, as are the reproductive instincts. As in
his zebra sire, there are large teats, but, unlike both sire
and dam, though doubtless like the ancestors of both, the
skin forming the scrotal sac has a complete coating of
hair ; this is doubtless another instance of regression.

But notwithstanding the fact that Romulus is apparently
as well developed as a horse of the same age, he has not
yet reached maturity, 7. e. his germ-cells are still incom-
pletely formed ; there is a head, but the merest rudiment
of a tail. This may, however, be accounted for by his
mixed origin. Though yearling colts and filles have

Ixxxvill GENERAL INTRODUCTION.

been known to breed, zebras never seem to reach maturity
until the fifth or sixth year. Hence, though zebra hy-
brids are not fertile as two-year-olds, they may prove
fertile when three or four years old. If one may judge
by the behaviour of the male germ-cells in other mam-
mals, it is possible that a change of the surroundings—
of the food, temperature, &c.—might make a profound
difference, transform a sterile hybrid into a fertile one.

Domestication is known to hurry on maturity. Ina
wild state it would be a disadvantage for a young
stallion to reach maturity much before his full strength
is required, until he has some chance of successfully
challenging the old leader of his troop, or forming for
himself a new one. It may safely be taken for granted
that the wild ancestors of our horses were Jater in
reaching maturity than their pampered domesticated
descendants. Hence, apart from any retarding influence
the zebra may have had, Romulus, in as far as he has
regressed towards his maternal ancestors, will presumably
be late in reaching maturity.

In- addition to Romulus, I have for some time had a
male zebra-ass hybrid under observation. This hybrid
having unfortunately died, I shall elsewhere be able to
describe at length the condition of the germ glands. In
the meantime I may, however, say that, as in Romulus,
the reproductive system of the three-year-old zebra-ass
hybrid seemed quite perfect, but, as in Romulus, the
germ-cells were incompletely developed, and hardly at
all mobile, owing to the tail being only on an average
twice the length of the head; in the horse and zebra
the tail is quite eight times the length of the head.
This condition of the male germ-cells is better described
as arrested development than as regression ; they closely
resemble a phase in the development of the corresponding
cells in the horse, but do not necessarily reproduce the
mature germ-cells in any of the ancestors of the Equide.
Whether, had this hybrid survived, ripe germ-cells would
have eventually appeared I am unable to say, and I am
also unable to say whether a different diet or different

GENERAL INTRODUCTION. Ixxxix

surroundings would have resulted in the formation of
perfect germ-cells.

I had some hope that this hybrid would be fertile, for
in its breeding it agreed with a hybrid (referred to by
Darwin and others) which is said to have had offspring
when mated with a pony. In the ‘ Gleanings from the
Knowsley Menagerie’ there is a figure (lix, 2) of this
triple hybrid, and at p. 73 it is described as follows :—
“The offspring of a mule (the produce of a male ass and
a zebra) with a bay mare pony. Iron-grey with a short
narrow cross-band on withers; very faint indications of
stripes on the sides, and more distinct dark stripes on
outside of the hocks and knees ; tail bushy from the base
like a horse, head heavy, mane brown and grey. This
animal used to draw a small cart. It stands eight hands
high.” Darwin, writing in the seventies, says of this
cross, ‘‘ Many years ago I saw in the Zoological Gardens
a curious triple hybrid from a bay mare by a hybrid from
a male ass and a female zebra.”

Not a few mistakes have been made. about hybrids.
There is, for example, the famous case of the fictitious
cross between the hare and the rabbit, and one occasion-
ally hears of a hybrid, equally improbable, between a dog
and a fox. Yet it is not likely Darwin would make so
pointed a reference to this triple hybrid had he not
satisfied himself that it was genuine. An effort is being
made in the gardens of the Melbourne Zoological Society
to induce a zebra-ass hybrid to breed. This hybrid is
certainly now old enough, and, with its genial climate,
Melbourne seems peculiarly well adapted for an experi-
ment of this kind. It need hardly be urged that the first
possible opportunity that offers should be taken to examine
the male germ-cells of ordinary mules and hinnies. This
could be best done where mules are common, and where
specimens of various ages are available.

Sterility of Female Zebra Hybrids.— Periodically it is
asserted in the Feld, or in some other newspaper, that a
female mule has produced a foal. Sometimes the inter-
esting event is said to have taken place in the Kast,

g

xc GENERAL INTRODUCTION.

sometimes in the West. Why it should always occur in
some out-of-the-way district is hard to explain. The last
account of a female mule having a foal comes from
India. The writer, Veterinary Captain W. D. Gunn, seems
to have satisfied himself that the mule is the real mother
of the foal in question, and not merely a foster-mother.
Mr. Gunn being a trusted and able member of his pro-
fession, we may perhaps assume that he has come across
an undoubted instance of a fertile mule. Unfortunately,
though he may have satisfied himself, he can hardly be
said to have satisfied the readers of the Meld. But it
will be well to allow Mr. Gunn to speak for himself ; he
says, “ A most unusual event occurred in the Kapurthala
State, India; indeed, it seems to be the only case on
record. A mule, belonging to a potter in the above
state, gave birth toa male foal on the day after its return
from the Tirah Field Force. Parturition occurred on
August 6th during the night, and on information being
given to the Prime Minister of the state, Sirdar Bhagat
Singh, C.L.E., he at once went to sce it early the follow-
ing morning. The greatest excitement has been caused
in the town of Kapurthala by this extraordinary occur-
rence, and the pundits are all at a loss to know what to
think about it. They say that such an event has never
been known before, and the Hindu shastras say that
whenever a mule becomes pregnant it must die before
giving birth to the young. Large crowds go daily to see
the mother and foal, and the pundits are consulting the
stars and shastras as to what is portended by the event.
“When Sirdar Bhagat Singh saw that the mule had
really dropped a foal he at once communicated with the
Civil Vetermary Department, and after making further
inquiries I proceeded to the Kapurthala State and took
the photographs which I send you by this post. Vete-
rinary Captain Joslen, officiating principal of the Lahore
Veterinary College, accompanied, and he will vouch for
the correctness of these statements. ‘The mule must
have been covered by a pony while proceeding with the
transport to the frontier war. As will be seen, the foal

GENERAL INTRODUCTION. xcl

is beautifully formed, and has the appearance of a pony
foal with very small ears. The mother is about twelve
years old, and stands 113 hands, and is a very typical
Indian transport mule.”

After referring to a number of doubtful cases of fertile
mules, he adds:

‘In the present case, however, there can be no doubt
about the genuineness. The foal was dropped at mid-
night, and was seen the next morning by large crowds,
including the Prime Minister, a Sikh gentleman of the
highest respectability.’’*

Every breeder knows that mules and young virgin
mares occasionally give milk, and also that foals are at
times enticed away from their mothers. Mr. Gunn may
have assured himself that the “ beautifully formed” foal
with “‘ very small ears’? has not been stolen by the mule
in question from a pony mare. Unfortunately this pos-
sibility is not referred to in his letter. Although my
experience is but limited, I have had an instance of a
foal being stolen by one mare from another, and also an
instance of a mare leaving her foal to take care of itself
immediately after it was born. Mr. Gunn, or his com-
panion Veterinary Captain Joslen, of the Lahore Vete-
rinary College, may be able to clear away all doubts; and
better still, the mule and foal may ere this have found
their way to one of the Government stud farms, where steps
will be taken to give the mule a chance of again breeding,
and where later the fertility of the foal will be tested.

Mr. Tegetmeier having long taken an interest in the
subject under consideration, it may be well to indicate
what he said on the subject about a year ago. In the
Field of October 23rd, 1897, he writes, “I have long held
the opinion that the ordinary equine mule of both sexes
is sterile. This, as is stated in the work on ‘ Horses
and Mule Breeding’ by Mr. Sutherland and myself, has
been founded on the great experience of M. Ayrault, and
the belief has been traced by us to the phenomena of
induced lactation in the mule mares, many of which have

* The Field, September 17th, 1898.

XCli GENERAL INTRODUCTION.

been known to suckle offspring not their own. At the
same time I am free to acknowledge that many cases of
strong evidence in favour of the fertility of mule mares
have come before us.’ After referring to a case he had
just heard of in Mexico, he proceeds to say, “This is one
of the most detailed accounts of a fertile mule that has
come under my notice.’ Mr. Tegetmeier, it will be
observed, does not say what he actually thought as to
the genuineness of any of the cases he had recently
heard of, but it may be inferred that in 1897 he was less
sure mules were invariably sterile than he was when
the work ‘Horses, Asses, and Zebras’ was published in
1895. As “little scientific observation has been brought
to bear upon the question of the character of the hybrids
between the horse and the ass,”’ I shall now state shortly
the results of recent observations on the reproductive
system of two female zebra mules, or, to be more
accurate, of a female zebra mule (zebrule) and a female
zebra hinny (zebrinny).

In my zebra-horse yearling hybrid, Heckla, which died
recently, the reproductive organs were found to be almost
identical with the corresponding organs in a young
Burchell zebra (which died about a year ago), and unlike
in various respects those of a mare. Heckla thus in-
herited her reproductive system through her sire, not from
her dam, the Iceland pony. In a ten-year-old horse-
zebra hybrid which also recently died I found the repro-
ductive system resembled that of Heckla, but there was
this important difference, that one of the reproductive
glands contained one large and several small Graafian
follicles which closely agreed with the follicles in the
reproductive gland in the mare, and were, as far as I can
make out, identical with the germ sacs or follicles in a
six-year-old Burchell zebra. One of these follicles had a
diameter of 1} inches,—a ripe follicle in a sixteen-hands
mare has a diameter of about 12 inches. From the ap-
pearance of the follicle it may very well have contained a
nearly mature germ-cell (ovum).

While it may be safely inferred male germ-cells almost

GENERAL INTRODUCTION. xXclll

devoid of flagella or tails are not likely to be of any use,
it is practically impossible to say whether any given
female germ-cell would, if fertilised, develop into a new
individual. The fact, however, that in the oldest of the
two zebra hybrids examined there was a follicle enclosing
presumably a nearly ripe germ-cell favours the view often
advocated, that female mules are at least occasionally
fertile, and at the same time encourages us to believe
that the Kapurthala potter’s mule is the actual mother of
the foal found in her possession last August. I ought,
however, to say that a three-year-old mule (ass ¢ -horse 9
hybrid) from the New Forest has so far proved sterile
alike with Shetland and Welsh ponies, and with the
zebra 2 -ass $ hybrid already mentioned, and that a
nine-year-old zebrinny (horse-zebra hybrid) seems also to
be sterile with both Arab and Clydesdale horses.

I intended discussing in this introductory chapter the
habits and instincts of young foals, the rate of growth of
foals and hybrids, and the use of stripes in the Equide ;
but a consideration of these and other questions may very
well be deferred until I have completed the first part of
a memoir ‘On the Development of the Horse,’ and a
small work ‘On Zebras and Zebra Hybrids.’

I have, in conclusion, much pleasure in expressing my
great indebtedness to Lord Arthur Cecil, Mr. Wilfrid
Scawen Blunt, the Hon. Walter Rothschild, and Lady
Meux. I am also not a little indebted to Sir William
Flower, K.C.B., F.R.8., Mr. Oldfield Thomas and Mr.
Pocock of the Natural History Museum, London, Professor
Mettam, B.Sc., of the Royal (Dick) Veterinary College,
Edinburgh, Mr. Dixey, M.A., of Wadham College, Ox-
ford, and Professor Stewart, F.R.S., of the Royal College
of Surgeons’ Museum, London. To Mr. Alfred HE. Pease,
M.P., Mr. Rowland Ward, Mr. Arthur H. Neumann, and
Mr. C. V. A. Peel I owe my best thanks for the loan of
valuable skins; and I must add that I owe much to the
writings of Mr. Darwin, Mr. Tegetmeier, Sir Walter
Gilbey, Bart., and Herr von Nathusius.

PART I.

A—THE BIRTH OF A HYBRID BETWEEN
A BURCHELL’S ZEBRA AND A MARE.

THE BIRTH OF A HYBRID.

In a note on Telegony,* published in 1895 in The
Veterinarian, I suggested a number of experiments which
might be made with a view to settling, if possible, whether
@ previous sire has any influence on subsequent progeny
obtained by other sires. At the same time I mentioned
that I was making arrangements to carry out three of the
experiments suggested, viz. (1) To cross a number of
mares with a male Burchell’s zebra, and then mate them
with an Arab or other suitable horse. (2) To cross a
zebra mare with an Arab horse, and then mate her with a
zebra. (3) To cross an ass (Hquus asinus) with a zebra
horse, and then mate her with a jackass.

Having begun in 1894 to make arrangements for the
telegony and other investigations, I was in a position early
in 1895 to begin operations,—that is to say, I had secured
a large area of grass land and a small paddock, pro-
vided accommodation for and purchased three Burchell’s
zebras (a horse and two mares), an Arab horse, and a
number of mares, including a thoroughbred filly by
“Petrarch,” a mare by ‘‘Gunboat,”’ and mares from
Ireland, Iceland, Shetland, and Norway. Further, Mr.
Wilfrid S. Blunt, on hearing of the proposed experiments
through the late Professor Goodhart, was generous enough
to send me an Arab mare (“ Bernabit”); and Lord
Arthur Cecil, whom I had the good fortune to interest in
my work, lent me ‘ Mulatto,” one of his Island of Rum
ponies, and later added to my stud a young New Forest
donkey.

It is hardly necessary to point out that even should the
experiments in hand settle, or at least throw new light on
the question of telegony, final results are not likely to be
gained until several years have elapsed. However, as the

* Appendix.

4. HE PENYCUIK EXPERIMENTS,

investigations are not limited to testing the influence of a
previous sire, but either directly or indirectly deal with
the development and ancestral history of the horse, with
reversion or atavism, and polydactylism, and with various
other problems of a more or less interesting nature, it
may be well to put on record now some of the events that
have happened since the work was started.

The Birth of a Zebra Hybrid.—The most interesting
event I have to chronicle is the arrival of a hybrid
between my Burchell zebra stallion (Matopo) and the
West Highland pony (Mulatto). The hybrid, which, as
announced in the Fteld,* was born on the 12th of August,
appears to be the first cross obtained between an ordinary
mare and a Burchell’s zebra stallion. Partly on this
account, and partly because zebra hybrids may help to
solve the transport difficulties in various parts of Africa,
and do something towards overcoming the aversion for
mules that has so long prevailed in England, a short
account of the new arrival may not be unacceptable. But
before speaking of the hybrid colt I ought to say a few
words as to his parents. There are still three zebras found
wild in Africa—two mountain zebras (EH. zebra and E. grevyi)
and the zebra of the plains (#. burchelli). The sire (Fig. 1)
of the hybrid, which belongs to the Burchell group of
zebras, I obtained from the Antwerp Zoological Gardens.

Mr. G. R. de Courcy-Perry, H.B.M.’s Consul-General at
Antwerp, to whom I am indebted for timely help at a
critical moment, reported that the directors of the gardens
considered their zebra stallion a superb animal; he is
certainly the most handsome specimen I have ever seen.
While in Antwerp “ Matopo” proved a successful sire,
but it was only found possible to mate him with zebras of
his own species. However, as a zebra long expected from
South Africa never arrived, and as the Antwerp one was
the only available mature male Burchell’s zebra in Europe
at the time, I had either to secure him or give up the
experiments for another year.

* The Field, August 22nd, 1896.

THE BIRTH OF A ZEBRA HYBRID. 5

Matopo, last summer (1895), was certainly very fasti-
dious ; instead of a large crop of foals I am only able to
report the arrival of one; but as a cross between a male
Burchell’s zebra and a mare has apparently not been hitherto
obtained, I ought perhaps to be thankful that the telegony

Fie. 1.

Matopo.

experiments did not prove a complete failure. By carefully
studying the habits of the zebra mares and Matopo all the
difficulties have been practically overcome ; he no longer
reminds one of the proverb, “ You may lead a horse to the
water, but you cannot make him drink.” I need only add
that the zebra horse, though low at the withers, stands

>

6 THE PENYCUIK EXPERIMENTS.

nearly thirteen hands high ; that he is beautifully marked,
and in his form and movements suggests a horse far more
than either of the mountain zebras; further, his action
when trotting is even more perfect than that of his stable
companion the high-class Arab horse Benazrek.
Mulatto (Fig. 2), the dam of Romulus, is a West High-
land pony, thirteen hands (52 inches) high. Lord Arthur
Cecil, who has taken a lively interest in the investiga-

Fic. 2

Mulatto.

tions from the outset, first intended sending a couple of
New Forest ponies. After further consideration he, for
various reasons, selected Mulatto; this has proved a
fortunate selection. Apart from the all-important fact
that Mulatto has produced a foal to the zebra, she is in
many ways pre-eminently suitable for the experiments in
hand. From information kindly supplied by his lordship,
it appears that the breed to which her sire belongs has
been for many years all but completely isolated on the

THE BIRTH OF A ZEBRA HYBRID. 7

Island of Rum, a small island lying between the mainland
of Scotland and the Outer Hebrides. As far as is known,
fresh blood has only once been introduced during recent
times into the Island of Rum. This was in 1848, when
the then proprietor of the island, the late Marquis of
Salisbury, sent to Rum a stallion belonging, it is believed,
to the characteristic West Highland strain. Mulatto’s
dam came from the Long Island (Outer Hebrides), but
she belonged to the same breed as the sire. Like Mulatto
and all her ancestors, as far as they can be traced, the
dam was almost black, and, like the majority of this par-
ticular breed of ponies, her eyes were of a hazel colour—
not brown, as in the majority of horses. In Mulatto there
is only a faint indication of the characteristic hazel-coloured
iris. It is difficult to account for the existence of more or
less isolated troops of well-bred ponies in the Western
Highlands. The late Marquis of Salisbury believed that,
notwithstanding their colour, they had Eastern blood in
their veins. It has been suggested that they numbered
amongst their ancestors horses which escaped from the
ill-fated ships of the Spanish Armada. In support of this
belief it may be mentioned that an old tapestry in the
House of Lords (a representation of which appeared some
years ago in the Illustrated London News) indicates that
storms overtook the Spanish fleet at several points off the
Western Islands. It may be more than a coincidence that
well-bred ponies were afterwards found on islands adjacent
to the storm areas—on islands and parts of islands to which
the dismantled Armada ships might very well have drifted.
Further, the Mulatto breed of ponies resembles well-bred
black horses often met with in Spain at the present day.
Whatever the origin of the ponies in question, it is enough
that they belong to a distinct breed, and that probably
only once (in 1848) during many generations has fresh
blood been introduced into the isolated and somewhat inac-
cessible Island of Rum, from whence Mulatto’s sire was
exported in 1888. As a proof of the isolation, or, in other
words, of in-breeding, crosses between Island of Rum

8 THE PENYCUIK EXPERIMENTS.

ponies and other breeds present nearly all the characters
of the West Highland race. _

Mules generally strongly resemble their asinine pro-
genitors, but the mules bred by the late Marquis of Salis-
bury in the Island of Rum were observed on reaching
Hatfield to resemble ponies rather than donkeys. ‘This, to

Fic. 3.

Romulus (seven days old) and his dam, Mulatto.

my mind, proves that Mulatto belongs to a well-marked
and distinct breed, and that whatever the result may
eventually be, she is in every way as suitable, as well
adapted for taking the place of the nearly purely bred
Arab mare used in Lord Morton’s famous experiment, as
the zebra Matopo is an excellent substitute for the now

extinct or all but extinct quagea. It is only necessary to

THE BIRTH OF A ZEBRA HYBRID. 9

add, before proceeding to describe the hybrid, that the
foals of the black Highland ponies are frequently at first
mouse-coloured, with in some instances a faint dorsal
stripe, and a patch of dark hair at the shoulders, which
represents the bands so often seen in dun-coloured Nor-
wegian ponies. The dorsal stripe usually disappears soon
after birth, and the mouse-colour never reappears when
the first or foal’s coat is once shed.

Turning now to the hybrid, I may first mention that the
period of gestation was normal, 342 days. With the mare

Fie. 4.

Romulus, twenty-seven days old.

it usually varies from 340 to 350 days. In the zebra, as in
the ass, it is said to extend over twelve months. Within a
minute after birth the hybrid (fig. 3) was rushing about as
if he were a young zebra, whose existence depended on his
at once joining the troop of which his dam was a member.
Being extremely alert, and ready to gallop off at any
moment, he seemed at a loss to understand the inaction of
his placid dam. Though wher nearly a month old (Fig. 4)
Romulus was no longer so restless, or like a timid young
animal whose only safety was in flight, he was still surpris-

10 THE PENYCUIK EXPERIMENTS.

ingly energetic, and he seemed to enjoy nothing better
than coursing about his paddock as if he were escaping
from some dreaded foe. He is now wonderfully tame, and
courts rather than shuns notice; and from the first he has
behaved himself quite differently from a young New Forest
mule I had the opportunity of constantly watching during
last summer. In nearly all his movements Romulus
resembles his sire rather than his dam; he has not the
dainty action of a young mule or a young donkey, and yet
he differs in his gait from a horse. As he grows older I
anticipate the beautiful action of the zebra will become
more and more apparent. The Arab mare, Bernabit, when
set free in the field carries her head high in the air ina
most suggestive way as she gallops about. The zebra
horse, on the other hand, carries his head low, and twists
his neck as if engaged in single combat, ready to seize the
limbs of an adversary. In his gambols the hybrid carries
himself like a zebra, and this without once having had an
opportunity of seeing Matopo disporting himself.

When in the field with mares the zebra horse herds
them most jealously ; when anyone appears on the scene
he gallops along uttering his war-cry, prepared to defend
his troop against all comers. I shall not be surprised
should Romulus imitate his sire in this also, should an
opportunity offer by-and-by.

As the time drew near for the birth of the hybrid I
became more and more curious as to which of its parents
it would most resemble in shape and colour. When two
distinct types are crossed the progeny may present the
characters of both parents, or may closely resemble one of
the parents, or by reverting towards the ancestral type
differ decidedly from the immediate ancestors. For
example, mules sometimes closely resemble donkeys, at
other times they resemble ponies. Again, when a fantail
is crossed with a pouter, the young sometimes resemble a
blue rock, the supposed remote ancestor of all the pigeons.
There has probably been no intercrossing for many
thousands of years between zebras and the other wild

HE BIRTH OF A ZEBRA HYBRID. 11

Equidz, and it is quite possible there has not even been
interbreeding between the Burchell and the other zebras.
On the other hand, there is always a chance that any
given zebra has been inbred. Horses, on the other hand,
with a few possible exceptions, have been interbreeding
in all parts of the world; and though sometimes inbred,
they are usually supposed to be far less fixed and stable
than the zebras. Consequently, on a priori grounds, I
expected the hybrid to resemble at least in colour a zebra
rather than a horse. I had no very decided opinion as to
the shape of the hybrid, but I did not believe what some
would-be prophets asserted, that the only result of my
experiments would be the production of a monster ; that
it was little short of sacrilege to cross a good mare with a
zebra. Whatever form or colour the hybrid may ulti-
mately assume, I have no hesitation in saying that it would
be difficult to imagine any more attractive, more graceful,
or more beautiful member of the equine family than the
little hybrid Romulus during the earlier months of his
existence. .

Never ungainly, Romulus when two months old looked
as complete and compact as a little horse, and at least twice
his age, notwithstanding his being a late foal and the un-
toward weather that prevailed after his appearance on the
scene. ‘his is probably partly due to his beginning to
feed on his own account at a very early period. When
three days old he was nibbling grass ; a few days later he
attacked hay, and ere long he insisted on having a share
of the oats provided for hisdam. Foals frequently content
themselves with milk alone during the early weeks.

In shape the hybrid unites the characters of both his
parents, and yet without approaching a mule differs from
both. When standing on the alert at a little distance, he
looks (Fig. 4) as if he had slipped down from a frieze on
the Parthenon. The muzzle is very fine, with narrow,
almost slit-like nostrils of a distinctly zebra pattern. The
forehead is wide as in an Arab, and very slightly convex
from side to side. The jaws look narrow, and the head

12 THE PENYCUIK EXPERIMENTS.

seems to be set on the neck in an uncommon fashion, but
the neck is somewhat short. In the neck and its relation
to the head, in the position and length of the ears, and in
the mane, the hybrid undoubtedly approaches more closely
to a zebra than a horse. But beyond the root of the neck
I fail to observe any essential difference from a half-bred
Arab foal occupying an adjacent box. Both the fore and
hind quarters are well formed; the back is short and
strong, and the chest is wide and well moulded. In the
form of the fore and hind limbs, and in the hoofs, Romulus
also resembles in some respects the half-bred Arab, in
others his zebra sire; and his tail, with the exception of
several bands at the root and the presence of somewhat
stiff hairs, agrees with that of an ordinary foal. As in
the zebra, there are rudimentary teats, the chestnuts (warts)
are absent in the hind limbs, and further there is no tuft
of hair at the fetlocks. A little in front of the upright
mane there is a separate tuft of hair as in the zebra, and
as in many, if not all foals.

The Colour and Striping of the Hybrid.—Darwin, who
devoted much time to studying the colour of the horse,
came to the conclusion that all the existing races had
descended from ‘a single dun-coloured, more or less
striped, primitive stock, to which our horses occasionally
revert.”* In Dzungaria there appear to be still wild
horses, i.e. horses whose ancestors have never been domes-
ticated. The wild horses of North America, which are
believed to have descended from the Spanish horses of
Mexico, were of all colours—black, roan, sorrel, &c.; but
the Dzungaria horses are all of one colour. In summer
they are dun or sandy coloured ; in winter light brown.
In all probability the Dzungaria wild horse (E. przewalskii)
has not departed greatly in colour from the less remote
ancestral horse of the northern hemisphere. The absence
of shoulder and leg bands on these wild horses is interesting.
We shall never get beyond guessing when the stripes first

* «Animals and Plants,’ vol. i, p. 65.

9

THE BIRTH OF A ZEBRA HYBRID. 18

appeared in the horse group, but it may be assumed that
it was long before the days of Hipparion and his other
three-toed relatives.

Compared with the even-toed ruminants (oxen, sheep,
deer, antelopes, &c.), the odd-toed ungulates suffered
heavily during the Tertiary period—only the tapir, the
thinoceros, and the horse families have survived. This
being the case, it may be taken for granted that at least in
some areas the struggle for existence in the case of the
non-ruminating ungulates has been very keen. Bearing
this in mind, the existence of stripes becomes intelligible
if it be admitted that they counted for something in the
battle of life. While admitting that the ancestor of all
the horses was “more or less striped,” it is well to
remember that the only wild horse we are acquainted with
(#. przewalskit) has but a faint dorsal band; and that
while stripes were presumably useful in races living in
wide, fertile, richly populated plains, they may not have
been specially useful in the case of the Dzungaria and
other races living in remote desert regions.

In considering the colour of the hybrid it will be well to
remember that when distinct types are crossed the progeny
are apt to revert to a more primitive type, to assume some
of the ancestral colours.

Taking these and other facts into consideration, I ex-
pected the hybrid at birth to be of a dun or bay colour,
with distinct dark stripes on the legs and shoulders, and
less distinct stripes on the face. Bearing in mind the all
but complete absence of stripes in Lord Morton’s quagga
hybrid, I was not a little surprised when I found Mulatto’s
foal extremely well provided with stripes all over (Fig. 4),
in some respects more richly, if less obtrusively, decorated
than any of the zebras. As might have been anticipated,
the majority of the stripes were dark brown, while the body
colour varied from a light bay colour on the lower part of
the legs to a rich orange on the upper part of the face.
On the under aspect of the neck and trunk, however, the
stripes were indistinct; this was especially true of the

14 THE PENYCUIK EXPERIMENTS.

ventral mesial band which blended with the dark body
colour at each side. When the markings of the hybrid
are carefully contrasted with the stripes in the Burchell
group of zebras, they will be found to differ very con-
siderably, more especially in the head region and over the
loins and hind quarters. In the meantime I shall content
myself with shortly describing the disposition of the
stripes in the hybrid. ‘The forehead is characterised by
having a remarkable series of dark brown narrow bands,

Fie. 5.

E>7

Romulus, twenty-seven days old.

which alternate with a corresponding series of equally
narrow orange-coloured bands. Beginning on a level with
the eyes these bands extend upwards, forming a number
of graceful arches (Fig. 5) which at once remind one
of the forehead of an elaborately tattooed Maori chief,
Fourteen pairs of these bands can easily be made out, but
the upper ones are interrupted by the tuft of hair which I
have named the frontal tuft. Curving downwards from

THE BIRTH OF A ZEBRA HYBRID. 15

between the eyes towards the nostrils are other bands of a
similar width and colour, which serve to decorate the front
and sides of the face. These stripes eventually lose them-
selves in the rich brown hair above the level of the nostrils.
The somewhat lozenge-shaped space in the centre of the
forehead, 7. e. the space between the lateral curved bands
just mentioned and the loops above the eyes, is occupied
by a U-shaped loop, one end of which bends upwards,
while the other, accompanied by a nearly mesial stripe,
runs for some distance down the middle of the face.
Similar bands (twelve dark and twelve light) extend from
the base of the ear obliquely downwards over the jaw.
The greater part of the head is thus tattooed with bright-
coloured narrow stripes arranged in a quite unique fashion.
In having this complex arrangement of narrow dark and
light bands over the face, the hybrid differs in a striking
manner from his sire, but approaches some of the East
African and Somali zebras.

The ears, though zebra-like in shape, are not, as in the
zebra, distinctly banded. In a light bay Shetland pony in
my possession the tip of the ear is white as in the zebra,
but in Romulus the upper third of the ear is of a dark
brown colour. This colour extends as a broad band
towards the base, where it is interrupted by tan-coloured
bands having in the main a transverse direction. The
ear is lined with a thick coating of long, fine, bright yellow
hair. In a front view the light-coloured ears, with the
dark upright mane between them, are almost as conspicuous
as the corresponding structures in the zebra.

As is usually the case in zebras, a dark band extends
downwards from the withers, to bifurcate at the shoulder,
the one limb running forwards to the chest, the other
backwards behind the elbow. In front of this, which may
be known as the shoulder stripe, are a number of cervical
stripes, some of which blend as they run across the neck.
At the root of the mane, between the shoulder stripe and
the occipital crest, over twenty dark bands alternate with
a corresponding number of light ones. The latter are

16 THE PENYCUIK EXPERIMENTS.

continued some distance into the mane by light brown
hairs. The last pair of cervical bands meet, as in the
zebra, in the middle line over the sternum, and become
continuous with a broad but not very well-defined ventral
band, consisting of long dark brown hairs. Running
downwards across the trunk, behind and nearly parallel
with the shoulder stripe, are nine bands, which take the
place of the four or five broad vertical bands in Burchell’s
zebra. Behind these are a number of oblique bands
which curve upwards and backwards, the lower extending
across the hind quarters. In the space between the
vertical and oblique bands are a number of indistinct
narrow stripes, while over the croup and rump there are
rows of spots. In having these spots and narrow stripes
over the hind quarters and loins the hybrid differs from
all the zebras.

It will be interesting to note if there is a like failure to
develop distinct broad bands over the hind quarters in
hybrids that may afterwards be obtained. The remark-
able decoration of the hind quarters is more likely to be
due to reversion than the elaborate decoration of the face.
It may even have some relation to the dappling so common
over the hind quarters in most breeds of horses. There is
a distinct dark dorsal stripe, with a yellow line at each
side, extending along the spinal ridge to the root of the
tail. The dorsal band, narrow in front, expands con-
siderably as it proceeds backwards. The tail, as in the
zebra, has several cross-bars at its root. In the region of
the shoulder-joint there is again a failure to form distinct
stripes, but there are numerous bands across both the fore
and hind limbs. Twenty-four bars were counted on the
left fore-limb, and thirty-one on the left hind limb. ‘The
twelve below the “knee” run obliquely downwards and
backwards, and become fainter as the fetlock is reached,
while those on the “knee” and the forearm are well marked,
and almost form complete circles. In the hind limb the
bands above and for a short distance below the hock are
extremely well marked, while those on the shank and over

THE BIRTH OF A ZEBRA HYBRID. 17

the fetlock and pasterns are only represented by faint,
short, oblique bars, which fail to reach the inner surface.
As in the zebra, there are narrow incomplete “shadow ”
stripes dividing the broad spaces between the well-marked
dark bands of the thigh and upper part of the leg.
Without giving further details it will be evident, with

Fie. 6.

Matopo.

the help of the figures, that the hybrid is elaborately
striped, and that it profoundly differs from an ordinary
foal. If the figures of Romulus are compared with Figs.
1 and 6—reproductions of photographs of his sire Matopo—
numerous differences in the disposition and in the number
of the stripes will be readily noticed. Should the next
foal, as was said to be the case in the purely bred second
2

18 THE PENYCUIK EXPERIMENTS.

and third foals of Lord Morton’s mare, be still more
banded, or even provided with a fraction of the bands
seen in the photograph, a very good case will have been
made out for telegony.

It is still impossible to say what colours the hybrid will
eventually assume, but I believe a number of the bands
will all but disappear, and that the dark stripes will be
separated from each other by bay or dun-coloured spaces.
It is quite possible that hybrids bred from light-coloured
mares may retain a light body colour and, even when full-
grown, have the stripes as distinct as a zebra.

Before leaving the hybrid I may point out that its
existence raises a number of interesting questions. In
1808 Frederic Cuvier published in the Annals du Muséwm
@ Histoire Naturelle* a note on the mating of an Arab
horse with a zebra mare which had previously bred with a
male donkey. Unfortunately the mare died some months
before the period of gestation was completed. Since then
several hybrids have been bred between zebra mares and
ponies, but apparently a hybrid between a pony mare and
any of the members of the large Burchelli group of zebras
has not hitherto been obtained. Mules, i.e. hybrids
between a jackass and mares, are alike common and
valuable ; while hinnies, 7. e. hybrids between a pony and
a she-ass, are rare in England, but comparatively common
in Ireland. While hybrids between ponies and zebra
mares may not prove specially useful, hybrids between a
zebra stallion and ordinary mares (what some would call
zebra mules) may have a great future before them. Cap-
tain Lugard, who has done splendid pioneer work, more
especially in Hast Africa, recommended some years ago
“that an attempt should be made to obtain zebra mules
by horse or donkey mares,” because he believed such
mules “would be found excessively hardy, and imper-
vious to the fly [the dreaded tsetse fly] and to climatic
diseases.”

* Vol. ii, p. 237.

THE BIRTH OF A ZEBRA HYBRID. 19

Captain Lugard believed “that their export might
prove one of the sources of wealth and revenue in the
future ;” for, as he adds, “ everyone knows the paucity of
mules, both for mountain batteries and for transport
purposes, has long been one of the gravest difficulties in
our otherwise almost perfect Indian Army corps.”* Like
Mr. Tegetmeiert, I have been assured that zebra mules
would be great favourites with the natives in India, and
further, it is supposed they might prove invaluable in the
West Indies. I have already mated seven different breeds
of mares with the zebra, mares varying in size from 11 to
15 hands, and, in fact, enough has been already accom-
plished to show that zebra hybrids could be produced,
suitable, as far as make and size go, for all kinds of work.
Further, I had last summer a Burchell’s zebra filly that
was perfectly docile, in every way as domesticated as a
Shetland pony. Hence from a mental as well as from a
physical standpoint I fail to see why zebra hybrids should
not, if properly handled, prove as serviceable to man as
either mules or horses—in some circumstances even more so.

Another question of interest is, will the zebra mules
breed inter se, or with horses, zebras, or asses, or any of
their hybrids? This is a question which it is impossible to
answer until experiments have been made. Because ordi-
nary mules have never been known to breed in England it
is argued zebra mules must be infertile. But this does not
necessarily follow, for as zebras differ from donkeys, so
may zebra hybrids (even in the matter of fertility) differ
from mules. Darwin writes, “Many years ago I saw in
the Zoological Gardens a curious triple hybrid, from a bay
mare by a hybrid from a male ass and a female zebra.” }
This is a case of an equine hybrid (t.e. a male hybrid
obtained by crossing a zebra mare with a jackass) being
fertile when mated with a pony mare. Granting the infor-
mation given Mr. Darwin was correct, this case proves

* ‘Our African Empire.’

+ Live Stock Journal, 25th Sept., 1896.
{ ‘ Animals and Plants,’ vol. ii, p. 16.

20 THE PENYCUIK EXPERIMENTS.

that even in the horse family hybrids may be fertile, and
strongly indicates that very careful attempts should be
made to induce the new zebra hybrids to breed.

Turning from the zebra hybrid, the next most important
fact to chronicle is that, by taking advantage of the know-
ledge gained as to the habits of zebras, there is now in
some respects less difficulty and danger in using Matopo
for stud purposes than there is in using many ordinary
stallions. Matopo, it may be mentioned, has been trained
without applying any severe measures whatever, and
without making him less a wild animal than he was on his
arrival. By gentle treatment he has become quite tract-
able. Some days ago I observed the stud groom pulling
Matopo’s tail with the object of bringing him round to
drink. This is one side of the shield; but there is another,
for the same groom would be at once attacked, should he
interfere when mares are in the vicinity of the zebra.
Under such circumstances Matopo is quite regardless of
whips or other instruments of a like nature.

In concluding my remarks on the zebras I may mention
that, like Frederic Cuvier in 1807, I had no difficulty in
mating the five-year-old zebra mare with the Arab horse
Benazrek ; but unfortunately this mare succumbed during
the winter. The two-year-old zebra filly which I found so
docile and attractive also fell a victim to the dreaded para-
site Strongylus.

In addition to working with zebras I attempted various
crosses with donkeys and with an Indian (zebu) bull, but
so far I have failed to obtain any results.

In connection with my investigations bearing on poly-
dactylism and on the development of the horse I may
mention that I have now in my possession several speci-
mens showing extra digits in the horse and a considerable
number of horse embryos. Amongst others I have an
embryo for each of the weeks from the third to the eighth
inclusive. I have already shown* that in a horse embryo
fourteen inches in length the second and fourth digits

* Journal of Anatomy and Physiology, April, 1894.

THE BIRTH OF A ZEBRA HYBRID. 21

though extremely small, are present. I am now in a
position to state that at the fifth week the second and
fourth digits look nearly as long and as well developed as
the third or middle digit,—that, in other words, the horse
is for a time tridactylous, the outer digits being relatively
nearly as large as in the adult rhinoceros.

In addition to studying the embryos I have been ex-
amining the foetal appendages. The most interesting facts
made out in connection with these appendages are, first,
that the rudiments of the foetal villi make their appearance
between the sixth and seventh weeks, and are well formed
by the end of the eighth week; and second, that as the
yolk placenta dwindles, a complex epiblastic girdle appears
externally, while numerous apparently non-vascular villi
grow out from the allantois into the coelomic space between
the rapidly growing allantois and the yolk-sac.

Postscript.—I find I have omitted to mention that Ro-
mulus is Mulatto’s first foal, that his eyes are of a bluish-
grey colour, somewhat darker than in his sire, Matopo,
and that the hocks were for a time marked by narrow
longitudinal grooves.

Appendix.—Measurements of Romulus (in ches) when
two months old: withers to the ground, 383; shoulder-
joint to the ground, 29; elbow to the ground, 263; elbow
to the fetlock, 204; cannon bone along outside, 8; cir-
cumterence at knee, 8$; circumference below knee, 5;
withers on a line with anterior border of scapula to root
of tail, 271; withers to occipital protuberance, 19; chest
to buttocks, 85; girth behind fore-legs, 39; length of
head from occipital protuberance to end of muzzle, 163 ;
width between eyes where narrowest, 5}; where widest,
94; length of ear, 6; stifle to hock, 18; hock to ground,
18; circumference of fore pasterns, 5; circumference of
hind pasterns, 5}; circumference of shanks, 53; circum-
ference of fetlock-joints, 74; circumference of coronets 74.

B—ZEBRA-HORSE HYBRIDS.

ZEBRA-HORSE HYBRIDS.

Tue Zesra Sine or tHe Hysrips.

Durine the last two years* I have bred five hybrids by
crossing mares with a zebra stallion (Equus burchellc var.
chapmant). The first hybrid was born on August 12th,
1896; the others were born during the summer of 1897.
The dams of the respective hybrids are (1) an island of Rum
pony, (2) a Shetland pony, (3) an Iceland pony, (4) an Irish
mare, (5) a cross-bred Clydesdale mare.

The sire (“ Matopo’’) of all the hybrids is a handsome 12.2
hands Burchell’s zebra, probably from the Transvaal. As
Fig. 7 shows, Matopo is well formed, with powerful legs,
and for a zebra, a fine neck and fairly good shoulders.
In his movements he is almost perfect. When trotting the
fore-legs move gracefully, without suggesting the hammer-
ing action of the hackney; and when galloping he seems to
bound along as if without effort, and with but little expen-
diture of energy.

If zebras deserve the ill character they have hitherto
borne, Matopo must be an exception to the rule. We are
too apt to forget that until zebras have been under domes-
tication for some generations, itis unfair to judge them by
the horse standard, which after all is not so very high. I
have known several perfectly docile captured zebras, and I
have had in my possession a filly (taken when quite young
in the Transvaal) which from the first was as docile, tract-
able, and trustworthy as any pony that was ever foaled. I
have refrained from handling Matopo for obvious reasons,
yet there is never any difficulty in managing him, unless
when he is herding mares, or unusually excited. When in
a field with mares he is unapproachable, for, regardless of
consequences, he attacks all who venture into his vicinity.

* 1896 and 1897.

26 THE PENYCUIK EXPERIMENTS.

Galloping up open-mouthed, uttering his characteristic call,
he endeavours to seize intruders by the legs. On one
occasion, in a small paddock, he guarded a dozen mares so
well that it took four of us nearly two hours to drive them
into their boxes. He is, however, easily upset by unusual
noises, and there is nothing that drives him into a state of

Fie. 7.

Matopo.

frenzy so readily as carpet-beating, or that cows him so
effectually as a coil of rope. Ihave often wondered if the
rhythmic beating of carpets reminds him of the day when
in far-off Africa he lost his freedom—of the time when
Boers entangled his limbs to music made by Zulus beating
their shields with their assegais.

The more characteristic stripes of Matopo are seen in

ZEBRA-HORSE HYBRIDS. 27

Figs. 7 and 8. Fig. 8 shows a series of pointed brow
arches, some of which end in a frontal tuft nearly two
inches in length. Continuous with the frontal stripes are
a number of vertical stripes. These stripes extend to the
muzzle, the dark skin of which is sparsely covered with
short light hairs, except above the nostril, where there are

Fig. 8.

Matopo.

ill-defined dark brown “nostril patches.” There is usually
a distinct shoulder stripe in zebras, passing downwards from
the withers to bifurcate about the levelof the shoulder- joint.
In Fig. 8 the right shoulder stripe is seen to be double,
while in Fig. 7 the two shoulder-stripes have united for
some distance. Between the shoulder stripe and the occi-

28 THE PENYCUIK EXPERIMENTS,

pital crest there are usually twelve cervical stripes, all of
which run up into the mane to form, with a corresponding
number of white bundles, a series of black and white tufts.
Lying between the two upright rows of tufts, and continuous
with the dorsal band, is the mane proper, consisting of more
or less upright black hairs. The most anterior part of the
mane, instead of forming a forelock as in the horse,
extends beyond the level of the ears, and projects for-
wards at right angles to the long axis of the face. Behind
the shoulder stripe there are, on the left side, five broad,
nearly vertical stripes, all but the last reaching the dorsal
band above, while all but the first reach the ventral band
below. Behind the fifth vertical stripe are a number of
broad oblique stripes, with indistinct “shadow” stripes
between them. Of these oblique stripes, one, beginning at
the root of the tail, runs forward to pass over the point of
the ilium (hip) before bending sharply downwards to reach
the ventral band. I have named this the great flank
stripe. Below this flank stripe a second, having a similar
course, may be known as the intermediate flank stripe.
The intermediate stripe is followed by a third, which,
starting some distance below the root of the tail, runs
obliquely across the quarters to bifurcate over the stifle,
the anterior division proceeding towards, but not actually
reaching, the ventral band. This may be known as the
lower or stifle flank stripe. These three flank stripes are
equally distinct on the right side, the bifurcation over the
stifle being especially evident.

In the space formed by the divergence of the two
shoulder stripes or by the splitting of the single shoulder
stripe are several indistinct arches, and below these arches
are the transverse bars of the leg. In some cases this
V-shaped space contains portions of seven arches, and the
legs may be striped to the hoofs. Below the stitle stripe
there are first oblique and then nearly transverse stripes
across the hind leg, with sometimes shadow stripes between.
In Matopo the stripes are indistinct on the lower part of
the hind Jeg, but in many zebras they become more dis-

ZEBRA-HORSE HYBRIDS. 29

tinct and relatively broader as the hoof is reached. It
will be further observed from the figures—(a) that the
upper part of the tail is distinctly striped, and that only
the lower part carries long hairs; (b) that though there is
a large wart (chestnut) on the fore-leg, there is no rudi-
ment of a wart on the hind leg, and (c) that there is no
tuft of hair at the fetlock.

It may be mentioned that in no two zebras, or on the two
sides (Figs. 7 and 8) of the same zebra, is the striping alike,
that in some cases there are nearly as many shadow as
there are ordinary stripes on the neck and body; that even
in some of the Burchell zebras there are stripes across the
croup and rump. which suggest the “gridiron” of the
common zebra (H. zebra); and that while in summer the
dark stripes are nearly black and the light stripes cream-
coloured, in winter the dark stripes are occupied by fairly
long brown hairs, while the light stripes are made up of
equally long white hairs; the light tufts at the side of the
mane, however, are white summer and winter. It may be
added that Matopo, like the majority of the Burchell group
of zebras, being adapted for a life on the plains, has
rounded hoofs and comparatively short ears. He thus
differs from the mountain zebra (H. zebra), and from his
stable companion, a white Arabian donkey, in which the
hoofs are long and narrow, while the ears measure eleven
and a half inches, five inches more than in Matopo.

Tue Hyerip “ Romutus.”

The oldest hybrid (Romulus), as already noted, was born
on the 12th of August, 1896, the period of gestation being
342 days,—in the mare it is usually from 340 to 350 days.
The dam of Romulus was a thirteen hands black Island of
Rum pony, lent for the experiments by Lord Arthur Cecil,
of Orchardmains, Kent. The well-bred nearly black
ponies of the Scottish Western Highlands and Islands,
which have long been under observation, form a distinct
breed, well adapted in many ways for crossing with zebras.
Their resemblance to Eastern horses has been accounted

30 THE PENYCULK EXPERIMENTS.

for by saying that they have descended from sires which
escaped from the ships of the Spanish Armada.
Romulus, when a few days old, was the most attractive
little creature I have ever seen (Fig. 9). He seemed
to combine all the grace and beauty of an antelope and a
well-bred Arab foal. Instead of, like his sire, looking as if
freshly painted for a Lord Mayor’s Show, he was faultless

Fie. 9.

Romulus (seven days old), and his dam, Mulatto.

im colouring and in the disposition of the stripes, spots,
and bands. The body colour was chiefly of a bright
golden yellow, while the stripes and spots were of a rich
dark brown ; but what was especially remarkable was the
indescribable sheen of his coat, the dark bands being
especially lustrous. A casual glance showed that in the
plan of his striping Romulus was utterly unlike his sire,

ZEBRA-HORSE HYBRIDS. 31

and when a careful examination was made, it became
evident that in the number and arrangement of the
markings he was not unlike a Somali zebra. As Fig. 10
shows, the brow has been tattooed as if to represent a huge
finger print. Instead of the four or five acutely pointed
frontal arches of his sire, there are fourteen rounded
arches, that remind one of the face of the Somali zebra.
Instead of twelve cervical stripes, as in Matopo, there arein
Romulus twenty-four cervical stripes, all of which can be

Fie. 10.

Romulus: twenty-seven days old.

traced into the mane. In having so many cervical stripes
he seems to be more primitive than even the Somali zebra
(in which I have never seen more than fourteen cervical
stripes), but closely agrees with one of my zebra mares
when the shadow stripes are included. The shoulder
stripe bifurcates higher up than in Matopo, and there are
geven indistinct arches in the triangular space below the
point of bifurcation. Behind the shoulder stripe there are

32 THE PENYCUIK EXPERIMENTS.

nine (Figs. 9 & 11) fairly distinct vertical stripes instead of
five, as in his sire (Fig. 7). Apparently corresponding to
the three flank stripes so often seen in Burchell zebras,
there are in the hybrid three stripes in front of the stifle,
which first run upwards and then arch backwards to end
below the root of the tail (Fig. 9). Between the last vertical
stripe and the great flank stripe are three ill-defined

Eres. 11.

Romulus: one year old.

oblique stripes. In the triangular space between the first
oblique stripe and the ninth vertical stripe are numerous
narrow indistinct lines, some of which proceed towards
the ventral band, while others join the oblique stripes.
In line with these nearly transverse stripes there were at
birth numerous spots arranged in nearly transverse rows
over the loins and rump. Now that the hybrid is over a

ZEBRA-HORSE HYBRIDS. 33

year old (Fig. 11) most of the spots have united to form
somewhat zigzag narrow bands, almost identical in their
direction with the narrow stripes over the hind quarters of
the Somali zebra. On the left side the blending of the
spots has advanced further than on the right. Counting
from the shoulder stripe to the root of the tail, there are
forty-three stripes in the hybrid,—about the same number
as in the Somali zebra; in Matopo there are only five
transverse stripes behind the shoulder stripe (Fig. 7). It
seems to me the blending of the spots over the hind
quarters of Romulus goes a long way towards proving that
stripes are in many cases first represented by spots or
interrupted zigzag wavy lines. Between the stifle or third
flank stripe and the point of the hock there are a number
of dark bands (between some of which are shadow stripes),
while below the hock there are first several distinct trans-
verse bars, and then a number of less distinct oblique lines,
right down to the hoof. Similar bars and lines occur on
the fore-limb. These leg bars were at birth more distinct
than in the zebra sire. Continuous with the mane is a
well-defined dorsal band (with a narrow yellow band at each
side) which extends some distance into the tail. The tail in
the hybrid had, at birth, long hairs right up to the root, but,
notwithstanding this, there were three distinct bars visible
at each side; similar tail bars I have once seen in a horse.

Though the ears look long in some of the photographs,
they are now relatively very little longer (though rounder
at the apex) than in the majority of horses. The nostrils,
in their shape, position, &c., are zebra-like, and the eyes
and eyebrows may be said to be intermediate; but the
eyelashes are long and curved, and quite unlike the short
nearly straight eyelashes almost invariably found in zebras
and horses. The hoofs of Romulus suggest the zebra
more than the horse. They seem to be made of excellent
stuff, and to stand a good deal of wear. In his movements
the hybrid takes more after his sire than hisdam. A few
minutes after birth he was rushing about his box, impatient
apparently to join the parental troop. What has struck

3

34 THE PENYCUIK EXPERIMENTS.

me from the first has been his alertness and the expedition
with which he escapes from suspicious or unfamiliar
objects. When quite young, if caught napping in the
paddock, the facility with which he, as it were, rolled on
to his feet and darted off was wonderful. The principal
enemy of the zebra seems to be the lion. To escape from
the lion, great and sustained speed is not so requisite as a
decided and rapid bound when the lion makes his spring,
or when he is accidentally met with in the veld. This
rapidity of getting out of the way has been strongly
inherited by all the hybrids. Zebras, as far as my experi-
ence goes, are difficult to handle, not so much because
they are vicious or intractable, as because they are afraid.
At any moment they may be seized by panic,—when they
imagine there is a lon in the path,—and, regardless of
consequences, rush, it may be, against a wall or a hedge, or
into a ditch, reins and bits counting for little or nothing. In
schooling the hybrids this habit will require to be allowed
for, and the tendency to bound or rush slowly combated.
As it has been completely overcome by careful training in
some zebras, there should be comparatively little difficulty
in breaking the hybrids. .As a matter of fact, Romulus
leads anywhere, is perfectly docile, allows his feet to be
trimmed and his teeth to be examined, and, when little
more than a year old, seemed quite willing to carry a small
boy on his back.

I mentioned Mulatto is just under 13 hands, while the
zebra sire is nearly 12°3 hands. At birth (August 12th,
1896) Romulus measured 344 in. (from the withers to the
ground); at two months 38} in.; at six months 43 in.;
and at twelve months 45} in. The rate of growth has
been extremely inconstant, e.g. from the 12th of February
to the 12th of April, 1897, he only increased half an inch,*
and from the 12th of June, 1897, tothe 12th of September,
1897, he only increased three-quarters of an inch; + but

* He was weaned on the 14th of February, and fretted not a little for
some time after.

+ During the greater part of this period he was shedding his old and
growing a new coat.

ZEBRA-HORSE HYBRIDS. 35

from the 12th of September to the 12th of December,
1897, he increased one and a quarter inches. He now
(January, 1898) measures 47} in., nearly 12 hands, and
the circumference of the fore-shank is 6} in., the knee
being 10 in., and the girth 524 in.

The foals of the black Island of Rum ponies are fre-
quently of a mouse-dun colour, with at times an indistinct
dorsal band, and a cloudy patch over the shoulder. Usually
after the first coat is shed the pure-bred foals are dark
brown, and later nearly black, with sometimes indistinct
dappling over the flanks and hind quarters. As already
mentioned, the body colour of Romulus at birth was chiefly
of a yellow tint, the’ yellow approaching bright orange on
the brow, while it approached a straw colour at the muzzle
and below the knees and hocks. Under the neck and
under the belly the prevailing body colour was dark brown,
the ventral band being very indistinct.

The ears were lined with fine bright orange-coloured
hairs. When only a month old the hybrid began to shed
his foal’s coat. The light-coloured hairs began to drop
out from the face and neck about the middle of September,
and by the end of September he looked considerably
darker. The yellow and also the dark brown hairs con-
tinued to fall out, except over the back, all through
October, and by the middle of November only the orange-
coloured lining of the ears was left to remind one of the
rich coat he wore during the earlier weeks of his life. By
the end of November the new coat was established. The
bright orange facial bands were replaced by much paler
bands, the muzzle was nearly brown in colour, the neck
and body intermediate spaces approached a mouse-dun
colour, while the lower parts of the legs were of a dark
brown tint. From the withers to near the root of the
tail the hair was especially long and thick. For a time
the hair over the croup and the greater part of the rump
was so much longer than the hair around the root of the
tail that it looked as if part of the hind quarters had been
previously clipped. The new coat consisted of a thick

36 THE PENYCUIK EXPERIMENTS.

layer of woolly hair, from half an inch to nearly two
inches in length, and of a less complete coat of stronger
hairs, many of which were nearly three inches in length.
Near their roots all the body hairs were light in colour,
which implies that had the hybrid been clipped there
would have been little or no indication of stripes left. In
the zebra, on the other hand, the dark pigment extends
to the roots of the hair, and hence, however short the
hair may be, the banding is quite evident. Recently
the skin around the root of Matopo’s tail was injured,
with the result that the hair, together with some of
the epidermis, was shed; but even before the points
of the new hair could be detected, the position of the
dark bands was perfectly distinct. The skin of the
zebra has been described as uniformly black, even under
the white bands; but it would be more accurate to say
it is of a dark grey colour between the bands and
stripes, and nearly black where the bands and stripes
occur.

About the middle of March the long hairs began to
drop out, and by the end of March they came away in
handfuls. As the long hairs were shed from the body,
the long hairs were shed from the upper half of the tail,
with the result that for a time the tail of the hybrid was
little better covered than the tail of his sire. By the end
of May all the long hairs—light and dark—had vanished,
and early in June the dark and mouse-coloured woolly
hairs were coming out. By the 6th of June the dark
lustreless winter coat had sufficiently gone around the
base of the ears and above the eyes to indicate the colour
of the summer coat. All through June and July the
process of shedding continued, but by the 12th of August
—the hybrid’s first birthday—the summer coat was fully
established. The dark stripes, which consisted chiefly of
strong flattened hairs, looked very prominent. The inter-
mediate bands were of a reddish brown colour over the
brow, but elsewhere reminded one of the summer coat of a
stag. Taken as a whole, Romulus was very decidedly

ZEBRA-HORSE HYBRIDS. 37

darker as a yearling than during the early weeks of his
existence.

As the long hairs were shed from the body and the root
of the tail, numerous hairs dropped from the mane. In an
ordinary mule (the foal of a New Forest pony) which I
have had for some time, all the long hairs of the mane
were shed last summer; but in Romulus, either some of
the long hairs were retained, or the new hairs came in
before the old ones were lost. At any rate, though the
mane was shorter and less bulky and consequently more
upright during August, it always consisted of numerous
long hairs. At present the mane, which consists of wavy
hairs from seven to nine inches in length, tends to fall
slightly to one side,—the mane falls slightly to one side in
some zebras.

By the middle of September Romulus had again lost not
a few of the brighter coloured hairs, and since then he has
been getting again gradually darker. Probably because
of the extreme mildness of the season the long hairs have
already (January) begun to fall out in much the same way
as they did last March.

All the experts who have seen Romulus agree in con-
sidering him a decided improvement on his sire, and more
attractive and shapely than hisdam. Having been handled
from the first, he is, as a rule, extremely quiet. Occa-
sionally, however, he clearly indicates he has plenty of
courage and no lack of speed. At present he is par-
ticularly attached to a small thoroughbred mare. When
separated from this mare he is sometimes as restless as
his sire when upset by some change in his surroundings.
Last week a strange horse was galloped in the paddock
where Romulus happened to be for the day. The hybrid
became excited, and gave an excellent demonstration of
his trotting and galloping powers, and of how proudly he
can carry himself, and this continued for some time after
the intruder left the field. Romulus was recently described
by an excellent judge of horses in the Scottish Farmer
as “a bonnie colt, with rare quality of bone, ... and

38 THE PENYCUIK EXPERIMENTS.

with the dainty step and dignity of the zebra.’ There
is nothing about the hybrids, strange to say, that suggests
the ordinary mule or hinny.

Tur Hyerip ‘“ Revs.”

“Biddy,” the dam of Remus, is a three parts bred,
14°1 hands Irish mare. She has been in my possession
since 1893, and is now nine years old. Biddy is a bay
with black points, but no white hairs anywhere, and
Remus is her first foal. She is a very gentle, quiet creature,
and has always been in excellent condition, winter and
summer alike.

Evidently the zebra, before coming here, had not made
the acquaintance of any of his equine relatives. When
first introduced to Mulatto, he rushed into a corner with
his tail between his legs, and uttered peculiar little sounds
strongly suggestive of abject fear. Some of the ponies
rushed at him open-mouthed; others deliberately pelted
him with their heels. On the other hand, a bay Arab
stallion and various mares could not have been more
alarmed had he been a tiger, or, when he called ‘‘Quacha,
quacha,” a troop of lions. To give him a chance of
discovering what sort of an animal a horse is, I turned
him loose one evening with a good-natured but very plucky
bay Shetland pony. The pony proceeded to tease the
zebra, who very soon began to show fight. He was soon
circling round the pony with the object of seizing her legs.
For a time the pony was unprepared for this mode of
attack, but ere long adopted similar tactics, with the result
that the zebra was several times brought to his knees.*
After a couple of hours the duel came to an end,—the
damage being very slight on either side,—and ever after-
wards Matopo and “ Sheila” were excellent friends. But
even during the spring of 1896 the zebra was ridiculously

* I may mention that when his legs are touched with a rope or stick he
almost invariably drops on to his knees, or lies down altogether. This is,

I think, the result of his having been periodically thrown before he came
here that his hoofs might be looked to.

ZEBRA-HORSE HYBRIDS. 39

timid, and even now a very small demonstration leads him
to beat a hasty retreat. Biddy was the first fairly large
animal he ventured to approach. One day I tied her up
in a court about forty feet square, a cloth having been
previously bound over her eyes. The zebra in course of
time ventured within a few yards; later he laid his head
across her quarters, and then, for quite a long time, across
her withers. He next licked her lips, and ended by gently
nibbling at her ears. Evidently at length satisfied a big
horse was after all not so terrible an object, he retired to
his box and finished his corn. Having once learned the
peculiarities of a mare, he never forgets them. Some of
the mares he dislikes, while he is very fond of others,
getting quite excited when they pass his own particular
quarters, Donkeys, however, he completely refuses to
take the smallest notice of.

Remus—born on the 18th May, 1897—was, at birth,
relatively smaller and far less active than Romulus; the
period of gestation was three hundred and forty-six days.
When a day old he measured 354 in., his girth being 28 in.
On the 18th of June he had increased to 383 in., the girth
being 36in. When six months old he measured 447 in., the
girth being 474 in., the circumference at the knee 94 in.,
and below the knee 53 in. Romulus at six months old
was 42 in.

From the first Remus has been extremely friendly, and
yet in some respects he is more zebra-like than Romulus.
For some days he was little more than a machine,—an
automaton capable of following a moving object and of
sucking. All the special sense-organs were apparently at
work, but the brain seemed incapable of making much use
of the information collected. If I moved away he followed
me, and sucked at my fingers or anything else offered him.
He heard his dam when she called, but he was unable to
discover whence the sound came, and when he saw her ata
few yards distance he failed to recognise her. He seemed
to like aloes and water quite as much as sugar and milk, and
did not mind either strong smelling-salts or freshly-made

40 THE PENYCUIK EXPERIMENTS.

mustard. Though he kicked aimlessly when pinched, he
paid no heed to the application of either warm or very
cold substances to the skin. When a dog was first intro-
duced to Romulus, his excitement was intense. He rushed
about at a furious rate, striking as opportunity offered
with his fore-feet, holding his head high and stepping
high, as if moving through long grass, where other enemies
might lie concealed. Remus, on the other hand, when
two days old, allowed a yellow collie to lie down within
six inches of his muzzle, and only got up as a Dalmatian
approached, when a warning note was uttered by his
watchful parent. When the four 1897 hybrids and two
pure-bred foals were eventually weaned, Remus seemed to
mind very little. While one of the hybrids and a half
Arab foal were biting and kicking and rushing about as if
demented, Remus simply stood looking over the fence.
But by-and-by, when the others settled down, he set to
walking backwards and forwards behind the wall of his
court, exactly lke his zebra sire, and though he still
keeps this up as if he were a caged lion, none of the
others have followed his example. When Romulus was
weaned, he for some days rushed about, as much like a
zebra when highly excited, as his sire when upset by the
beating of carpets. Recently it was necessary to give the
hybrids milk containing thymol. The pure-bred foals
offered but little resistance, but all the hybrids fought till
they were exhausted, and nothing would persuade Remus
to swallow the first dose.

As might have been expected, Biddy’s foal is much
lighter in colour than Mulatto’s. With the exception of
the muzzle and the lower part of the legs, the body colour
is a rich light bay; the muzzle and legs were, at birth,
more of a mealy colour, but are now of a bay colour. The
bands are much lighter, and consequently less distinct
than in Romulus. As a rule they are of a dark reddish
hue, being especially evident on the brow, the forearms
and above and below the hocks. The plan of the striping
is the same asin Romulus; but even at birth several of the

ZEBRA-HORSE HYBRIDS. 4]

rows of spots across the croup had already united to form
narrow bands. The face, measured from the occipital
crest to a line connecting the upper margins of the nostrils,
was slightly longer than in Romulus; but the ears were
the same length—six inches.

Sometimes when a horse utters a warning call all the
members of the herd hurriedly collect together and rush
about in an excited manner. It seems to be of the utmost
importance for wild Equide to at once make out the direc-
tion of any given sound. Probably the longer the ears
the quicker this is accomplished. If the length of the
ears, aS is most probable, counts for much, one can
understand why they almost reach their full size at birth.
Foals are given to straying in all directions, and unless
they hear and at once recognise the call of their respective
dams, and the direction from which the sound comes, their
chances of surviving in a wild state would be greatly
reduced. At birth, the ears of Romulus were longer than
in his dam, and only slightly shorter than in his sire. In
the case of Remus they were the same length as in his
dam, viz. six inches along the upper aspect.

The eyes in Biddy’s foal are hazel-coloured and gazelle-
like in their mildness, and the upper eyelashes are particu-
larly long and curved. The mane, though at first made
up of soft hairs, which bent over to the right side, soon
assumed an upright position, and when Remus reached the
eighth month, it consisted of nearly erect but not very stiff
hairs. It looks as if the mane will always be as upright
and as short as in his sire. The tail contains fewer hairs
than any of the other hybrids, and has three bars across
the root. On the other hand, there are chestnuts on the
hind legs as well as on the fore; ordinary mules are said
not to have chestnuts on the hind limbs. The front
chestnuts are large, level with the skin, and zebra-like ;
the hind chestnuts are raised above the level of the skin,
and, though narrow and only half an inch in length, are
horse-like. That the zebras and asses have no chestnuts
on the hind legs may perhaps be due to the absence of

42 THE PENYCUIK EXPERIMENTS.

chestnuts in their remote ancestors; their absence points,
I think, to asses and zebras having sprung from a different
ancestor (perhaps Hipparion) than the horses, which may
have descended straight from Protohippus. If Remus sur-
vives, he may reach a height of nearly fourteen hands,
and be the most handsome and fleetest of all the present
crop of hybrids.

As in the case of zebra foals, the hair over the back and
hind quarters of Remus soon increased in length, and
formed a thick woolly covering. The hair of the first coat
usually falls off soonest from the face and neck, then from
the legs, especially at the knees and above and below the
hocks. Some of the hair was shed from the face by the
end of the first month, but there was still some left on the
muzzle and brow at the end of the third month, and the
legs retained some of the foal’s coat at the end of the
fourth month. The second coat, which was completed by
the end of the fifth month (7.e. about the middle of
October), consisted of a thick inner coat of bay and brown
fine wavy hairs, averaging an inch and half in length, and
of an outer but much less abundant coat of stronger hairs,
many of which were two and a half inches in length.
Neither the long nor short hairs nor the hairs of the
mane have yet (January) begun to fall out.

Tue Hyprip “ Brenpa.’’

The dam (“ Lady Douglas”) of Brenda is a cross-bred
Clydesdale mare, built on the lines of the “ Douglas ” breed
once common in the Hamilton district. Like Biddy, she
is a bay with black points, but, unlike the Irish mare, she
has a large “blaze” on the face, a heavy mane and tail,
and a liberal amount of hair at the fetlock-joints. Lady
Douglas is fifteen hands high, the circumference at the
knee is thirteen and a half inches, and below the knee
nine inches. The face is longer than in Biddy by nearly
an inch, and the ears by three quarters of an inch. I
expected Brenda (the Clydesdale’s first foal) to closely
resemble Remus in colour and markings; but in breeding,

7ZEBRA-HORSE HYBRIDS. 43

more especially in cross-breeding, the unexpected often
happens. We are too apt to forget that, even when the
sire belongs to a different and very distinct species, the
progeny may take after the cross-bred dam. It was
evident soon after Brenda (Fig. 12) was foaled that she
differed not a little both from Romulus and Remus. In
the first place her ears looked extremely long; they were
at birth six and a half inches, only a quarter of an inch

Fic. 12.

Brenda: two months old.

shorter than the ears of her dam, and quite as long as those
of her sire; at six months they were seven and a half
inches. On the other hand, the head is relatively short—
shorter than the head of a twelve-hands Iceland pony’s
hybrid. The height at the withers was forty-three inches,
one inch more than in Remus, and four inches more than
in the Iceland hybrid. At birth Brenda, apart from her
ears, looked not unlike an ordinary bay foal, but soon

44, THE PENYCUIK EXPERIMENTS.

faint stripes began to show themselves, and in a day or
two the stripes, though indistinct, were seen to closely
agree in their arrangement with those of the other hybrids.
Now that the “ Clydesdale” hybrid is nearly seven months
old, she at a little distance might easily be mistaken for
an ordinary foal. Compared with Remus the head is
shorter and finer, while the joints are larger and the
shanks thicker. At six months the circumference at the
knee was ten and a quarter inches, and below the knee
six and one eighth inches—almost exactly the same as in
Romulus when seventeen months old. The mane, at first
nearly upright, short and zebra-like, is now made up of
hairs from eight to ten inches in length (nearly as long as
in an ordinary foal of the same age). Except near the
withers and between the ears the mane arches freely to
the right side, some of the hairs almost touching the neck.
The hair between the ears already projects forwards to
form a forelock. In Remus, as already mentioned, the
mane is still upright, and shorter than in his sire. The
tailin Brenda has also from the first been heavier than in
any other of the hybrids, and fewer hairs have been shed
from its base; further, almost from the first there have
been a few hairs at the fetlock-joints. The hairs around
the small ergots are now over two inches in length.

The chestnuts on the fore-legs in the zebra are large
and smooth, and on a level with the skin; in Romulus
and Remus they are also large, and hardly if at all above
the level of the skin, but they occasionally give off thin
scales. In Brenda the front chestnuts, though relatively
nearly as large as in a zebra, project nearly as far above
the level of the skin as in a pure Clydesdale foal. The
left hind leg carries a small prominent chestnut about a
quarter of an inch in diameter, but there is no rudiment of
a chestnut on the right hind leg. The hoofs are the hoofs
of a zebra, and considerably smaller than would be the
hoofs of a Clydesdale foal of the same age. They are
wide behind and rounded in front, but the bars are rela-
tively short, i.e. they do not extend as far back as the

ZEBRA-HORSE HYBRIDS. 45

frog. I may add, the nostrils are in their shape a little
less zebra-like than in the other hybrids; that the muzzle
suggests the dam more than the sire, the lower lip being,
as in the dam, somewhat long; and that the rounded ears
are tipped with white, as is occasionally the case in dun
ponies as well asin zebras. As might have been expected,
the trunk and hind quarters are more massive than in
Remus, while the shoulders are less upright, and perhaps
as a consequence of this the action at all times is less
zebra-like than in any of the other hybrids. As Fig. 12
indicates, there is a ‘‘ swirl ” nearly three inches in length
extending down the centre of the face between the eyes.
The same figure also indicates fairly well the extent of the
marking at the end of the second month. The brow
arches (hardly visible in the figure) are nearly as pointed
as the frontal arches in a Norwegian pony in my posses-
sion, and as in the Amsterdam quagga. This is very
remarkable, as in all the other hybrids the brow stripes
form rounded arches. The cervical, and in fact all the
other stripes as faras they go, agree with the corresponding
stripes of Romulus. In the region of the shoulder the
markings are very faint, and over the hind quarters only a
few indistinct spots and portions of bands can be detected.
The lower part of the legs is only faintly striped, and even
the bars across the forearm and the hock are more obscure
than usual. But although none of the stripes are very
pronounced, there are, strange to say, faint lines between
several of the cervical and vertical body stripes. These
lines suggest “shadow” stripes, and seem to correspond
to some of the numerous indistinct vertical stripes seen in
zebra-ass hybrids. In having faint intermediate vertical
stripes, this, on the whole, horse-like hybrid may be said
to be, in at least one respect, more primitive than either
of the other hybrids already described. If this hybrid
continues to thrive, she ought to grow into a powerful,
active, shapely cob, about fourteen hands in height, hardier
and with more staying power than an ordinary mule.

46 THE PENYCUIK EXPERIMEN''.

Tur Hysrip “ Noretre.”

The most attractive of last sammer’s crop of hybrids
has for its dam a good-looking eleven hands Shetland
pony (“Nora”). This pony, which will be six years old
in the spring, had a foal in 1895 to a small black Shetland
pony (“ Wallace”). Nora is in many ways a small edition
of Mulatto, and her foal Norette may be said to be a small
edition of Romulus. When a few days old Norette, in
her colouring, movements, and make, was more fascinating
than Romulus at a similar age; and now that she has
increased from thirty inches, (her height when foaled on
June 8th) to nearly forty-one inches she looks as if she
belonged to some bygone age. Norette has been from
the first more intelligent than any of her contemporaries,
and always very much on the alert without being at all
nervous or frightened. She followed her dam through a
crowd of some thousands of people on Jubilee Day without
any hesitation or evincing any signs of fear, and she now
leads quietly and allows herself to be measured without
offering any resistance. At birth Norette generally
resembled Romulus, both in colouring, markings, and
shape, but her head was relatively smaller, and the ears
relatively shorter. There was, however, a very important
and interesting difference between Norette and the other
hybrids. As already pointed out, the croup and rump of
Romulus were at the outset marked by numerous rows of
spots having on the whole a transverse direction. When
his new coat was completed, in August last, I noticed that
many of the spots had united to form somewhat zigzag
bands which in their direction agreed closely with the
stripes on the hind quarters of the Somali zebra. In
Norette, instead of spots over the hind quarters, there
were from the first numerous narrow and hardly at all
wavy stripes, which line for line almost agreed with the
markings in the Somali zebra. But further, many of
these all but transverse stripes reached, or all but reached,

ZEBRA-HOKSE HYBRIDS. 47

a stripe running obliquely across the hind quarters in
almost the same position as the oblique stripe in the
Somali zebra, which I have elsewhere referred to as the
upper femoral stripe. The remarkable difference between
the markings over the hind quarters of Norette and her
sire Matopo, and the equally remarkable resemblance
between these markings in Norette and the Somali zebra,
seem to me to throw a flood of light on the relationships
of the stripes in the various species and varieties of
zebras, and at the same time strongly to support the view
already advanced, that the difference between the stripes
of the sire and his various hybrid offspring is in all
probability due to atavism or reversion. If this is the
correct explanation, it follows as a matter of course that,
at least in the markings, the Somali is the most primitive
of all the known recent zebras.

That the hybrids have reverted in at least their markings
towards a somewhat remote ancestor of the zebras is also
indicated by the presence of faint “shadow” stripes on
the neck. From Matopo having twelve cervical stripes
and some zebras having in addition nine or ten “ shadow”
stripes, and from Romulus having twice as many stripes
as Matopo, it may be inferred the typical number of
cervical stripes in zebras is twenty-four or thereabout.
But in Norette, in addition to the twenty-four cervical
stripes there were at least five faint “shadow” stripes.
In zebra-ass hybrids there are usually many indistinct
stripes on the neck and body, and numerous spots over
the hind quarters. I consider zebra-ass hybrids more
primitive in their markings than zebra-horse hybrids. In
having numerous cervical stripes Norette approaches
zebra-ass hybrids, and the only explanation of this that
occurs to me is that in Norette we have, in the striping of
the neck, a further reversion than in any of the other
hybrid offspring of Matopo.

During the first three months the mane of Norette was
quite upright, though thicker than in the other hybrids.
During the last four months the mane has been increasing

48 THE PENYCUIK EXPERIMENTS.

in length, and it is now no longer upright ; the posterior
half hangs over to the right side, the part between and in
front of the ears forms a thick forelock, while the inter-
mediate portion hangs to the left side.

Norette with her short head, peculiarly tattooed face,
and the heavy mane hanging partly to one side and partly
to the other, looks very quaint, and seems to differ quite
as much from her sire as she does from her dam the black
Shetland pony. Atseven months the coat was very heavy,
the long hairs of the body measuring over three inches,
while the hairs over the brow were nearly two inches in
length. If Norette develops after the fashion of Romulus,
she will—a year hence—be a compact small striped pony
from 11 to 11:2 hands in height. As is the case with
Romulus, there is nothing about Norette that suggests
either an ordinary mule or a hinny. She has excellent,
well-formed feet, only a few short hairs at the fetlock, and
not a rudiment of warts on the hind legs.

Tue Hyperip “ Hece.a.”’

Heckla’s dam is a twelve hands skewbald Iceland pony.
There is so much white in this pony (Tundra), and the
yellow is so pale, that I thought her hybrid foal would be
nearly as light as a pure-bred zebra. As it happens,
Heckla is the darkest of all the hybrids, and the stripes
were at birth as obscure as in the ‘‘ Clydesdale” hybrid
Brenda. As she lay by her dam shortly after birth, she
looked ke an overgrown hare with an unusually long
head and relatively long ears. From the first her coat
has consisted of long coarse hairs, and the warts on the
front legs are prominent, asin her dam. Measuring 324
in. at birth, she was 43 in. at six months, and is now
(January 12th) 433 in.; the circumference of the knee
being 93 in., and the fore-shank 5} in. Though Heckla
has always carried a heavy coat, and is dark in colour
with lght tips to her ears, she generally agrees with
Romulus in her build and markings; but her action

ZEBRA-HORSE HYBRIDS. 49

is freer, and more like that of a hackney than a zebra.
She promises to be quite as large and as active as Romulus,
and more able than Romulus to withstand cold and to
flourish under adverse circumstances.

The length of the head and the shortness of the neck
suggest that the Iceland ponies do not belong to the same
race as the black Oriental-looking West Highland ponies.
They may be direct descendants of the horses hunted by
the men of the Reindeer Period. Their ancestors may
have gradually worked their way northwards with the
Tundra fauna, which then, as now, lived near the edge of
the ice. If Heckla owes her dark colour to reversion, it
may be inferred her ancestors were of a mouse-dun colour.

It is too soon to offer any opinion as to whether Romulus
or any of the zebra-mare hybrids will prove fertile or
specially useful either at home or abroad, and it is equally
impossible to say whether they will withstand the African
tsetse fly, or have better constitutions than either ordinary
mules or asses; but this much may be said, they all seem
very hardy. Romulus has been in perfect health from the
first, as indeed has been his zebra sire, while nearly all my
mares and horses have had colds and other ailments.
Quite recently the four hybrid foals and three ordinary
foals have been suffering from the presence of various
species of Strongylus. One of the pure-bred foals
(Mulatto’s second foal to an Arab horse) died from the
effects of the parasite on the Ist of January, and a
thoroughbred foal has been reduced almost to a skeleton ;
but the four young hybrids, though no longer so bright or
in so good condition, are evidently rapidly recovering, and
will, I trust, be soon all right again. I may mention that
the editor of the Scottish Farmer believes Romulus “ will
be invaluable for driving or riding on account of his
hardiness,” and he has stated that all the hybrids “ have
feet and legs like whalebone, with the kind of pasterns
that Clydesdale men fancy.”’* It is well known that

* Scottish Farmer, November 27th, 1897.

50 THE PENYCUIK EXPERIMENTS.

Captain Lugard and Major von Wissmann have advocated
that steps be taken to breed zebra hybrids.

I have already referred to the views of Captain Lugard.
He writes:—“ Some years ago I advocated experiments
on taming the zebra, and I especially suggested that
an attempt should be made to obtain zebra mules by
horse or donkey mares. Such mules I believe would be
found excessively hardy and impervious to the ‘fly’ and
to climatic diseases. ... . I would even go further and
say that their export might prove one of the sources of
wealth and revenue in the future ; for, as everyone knows,
the paucity of mules both for mountain batteries and for
transport purposes has long been one of the gravest
dithculties in our otherwise almost perfect Indian Army
Corps.” Since this was written much information has
been gained as to the dreaded tsetse fly, but apparently
there is extremely little chance of horses being made
immune, being so treated by inoculation or otherwise that
they will be able to survive if once infected by the peculiar
minute organism so intimately associated with the all too
fatal disease.

Further, owing to the destruction of cattle by the
rinderpest, the transport difficulties have been increased
in Africa, while the frontier wars have enormously increased
the demand for mules in India. On the other hand, it has
been proved that it is a comparatively simple matter to
cross various breeds of mares with a Burchell zebra, and
if experts are to be trusted the hybrids (zebra-mules as
some call them) promise to be as useful and hardy as they
are shapely and attractive. The preliminary difficulties
having been overcome, it remains for those in authority
to take such steps as may be necessary to ascertain of
what special use, if any, zebra hybrids may be in the
various parts of the Empire, but more especially in Africa
and India.

As I am anxious to obtain as much information as
possible bearing on equine hybrids—on crosses between
zebras, horses, aud asses—and as to the fertility of the

ZEBRA-HORSE HYBRIDS. 51

various kinds of hybrids (mules, hinnies, &c.), I shall be
most grateful for accounts of any experiments hitherto
made, more especially with Burchell and other zebras. I
have not yet heard of ordinary mares having been crossed
with Burchell’s zebra in South Africa ; but doubtless some
of the readers of The Zoologist may be able to give me
information on this subject.

PART II.

TELEGONY AND REVERSION.

TELEGONY, WITH OBSERVATIONS ON THE
STRIPING OF ZEBRAS AND HORSES,
AND ON REVERSION IN THE EQUIDA.

INTRODUCTORY.

Or the still surviving ancient and widespread beliefs,
one of the most suggestive and interesting to students of
nature is the belief that parents hand on to their offspring
some of the peculiarities acquired during their lifetime; in
other words, that acquired characters or modifications—
characters not due to heredity—may be transmitted. This
is a tradition likely long to withstand the scotchings of
science, even should it, like so many other traditions, be
eventually found to rest on foundations of sand. The
transmission dogma may be said to consist of three main
stems or trunks, which are often associated with, and may
be named after, the patriarch Jacob, Lamarck, and Lord
Morton ; the heads borne by these trunks are, however, in
the meantime best left unnumbered and unnamed.

The Jacobean Trunk.—I have frequently heard of Aber-
deenshire farmers who acted as if they believed that were
peeled rods of hazel, poplar, or chestnut placed before their
cattle they would bring forth young “‘ring-straked, speckled
and spotted.” Amongst shepherds the belief is preva-
lent that if a single black ewe is allowed in the autumn to
run with a flock of white ones, however perfect their
pedigree, a considerable percentage of the next crop of
lambs will be black. Whether the methods at times practised
by breeders in various parts of Scotland to secure a desired
end are the result of observation and experiment, or are due
to a Boer-like faithin the teaching of the Old Testament, I am
unable tosay. But assuredly breeders of Aberdeen-Angus
cattle have not been singular in believing in the power of

56 TELEGONY AND REVERSION.

mental impressions on the offspring. The tradition influenced
the ancient Greeks ; it still holds sway in modern Rome.

The Lamarckian Trunk.—In 1801 and again in 1809
Lamarck ventured to suggest that the various species of
animals had not (as was then all but universally believed)
been separately and specially created. Like Erasmus
Darwin, he believed that from a few simple forms all the
varieties and species of animals had been gradually evolved.
He accounted for the progressive increase in organisation
in the vegetable and animal kingdoms by saying that as
new organs were needed they appeared—partly through
transcendental influences,—and that the modifications
acquired by one generation were handed on to the next.
In other words, Lamarck believed that the evolution of
plants and animals had been mainly accomplished by the
transmission of acquired characters, by the inheritance,
generation after generation, of functionally produced modi-
fications, together with changes resulting from the influence
of the surroundings or environment. To give the familiar
examples, Lamarck believed that the necks of the ancestors
of the giraffe had been lengthened by generation after
generation stretching them to reach the higher foliage ;
that webbed feet had been acquired in, e.9., aquatic birds
and mammals, by the toes being outstretched when swim-
ming; and, to take another example, Lamarck believed that
certain four-footed reptiles, by wriggling amongst shrubs
and grasses, by elongating their bodies and losing their
worse than useless limbs, had been gradually transformed
into snakes, while others by acting in a different fashion
had developed into birds. However incredible it may to
some appear, Lamarck’s theory in a modified shape still
forms part of the creed of not a few biologists in Europe
and of a still larger number in America. Some of the Neo-
Lamarckians may, like Lamarck, believe that improvements
partly result from the operation of some transcendental
principle working in predetermined lines—believe in a kind
of teleology.*

* It will, I think, be allowed that most people who come into touch

ra

TELEGONY AND REVERSION. 57

The Mortonian Trunk.—For all we know, breeders since
the days of the patriarchs may have believed not only in
the influence on the offspring of mental impressions, but
also in the influence of a previous sire; that the offspring
sometimes resemble not so much “ the father, but an early
mate of the mother,” and that the female comes to re-
semble more and more the male to which she continues to
bear offspring. We certainly know that what used to be
spoken of as the “ infection of the germ,” but which, fol-
lowing Weismann, we now-a-days call “ telegony,”* was
considered possible by physiologists at the end of the
seventeenth century ; we know the infection tradition has
long influenced Arab breeders, and that believers in this
hypothesis may now be found in every part of the world,
more especially wherever an overlapping of distinct races
occurs, as, e.g., in the Southern States of America and in
certain Turkish provinces. Further, until quite recently
many biologists considered that what is commonly and
conveniently known as Lord Morton’s experiment had
proved “infection of the germ” to at least occasionally
take place. Of these three main trunks I propose dealing
with the last, 7. e. with telegony, and with some of the re-
sults obtained by crossing zebras and horses.

Lord Morton's Bxperiment, and the Views of Darwin,
Weismann, and others.

It is admitted on all hands that the time has more than
come when the belief in the transmission of acquired
characters should be tested by carefully conducted experi-
ments. Already a number of isolated experiments have
been made without any decisive results, but (probably on
account of the difficulties to be overcome) no one has
hitherto repeated Lord Morton’s experiment. Weismann,
with nature, whether they admit it or no, are more or less teleologists ;
besides admitting that there are unfathomable mysteries, they, unconsciously
it may be, believe not only that there is order in the universe, but that a
kind of intelligence pervades nature.

* From raz, at a distance; and yévoc, offspring.:

58 'TELEGONY AND REVERSION.

who maintains that natural selection has been the only
influence at work in the evolution of all except the simple
unicellular organisms, has shown that the evidence in
favour of the transmission of acquired characters is in
many cases worthless, and in no case convincing.* In
discussing the “infection” theory in 1893, Weismann t
pointed out that new experiments after the manner of
Lord Morton’s were needed, and that they could “be best
made in zoological gardens.” t

Having failed to induce zoological or other societies to
take part in repeating Lord Morton’s experiment—work
which it was generally admitted should be undertaken
without further delay,—I decided in 1894 to start on my
own account a number of investigations bearing more or
less directly on telegony. I knew that numerous experi-
ments on this subject had yielded negative results, and
that some biologists held that such inquiries were all but
useless. On the other hand, I believed that by working
with zebras and horses I should obtain more decided results,
one way or the other, than with any other mammals, and
that, apart from any possible scientific gain, it was worth
while for various reasons attempting to produce hybrids be-
tween zebras and certain breeds of horses.§ I now propose
stating shortly the results of the experiments, as far as
they directly or indirectly bear on telegony and on rever-
sion or atavism. But before doing this it will be advisable
to discuss Lord Morton’s experiment, and refer to the

* See also Platt Ball, ‘The Effects of Use and Disuse,’ 180.

+ ‘The Germ-plasm’ (Contemporary Science Series).

{ Perhaps the time may come when systematic experiments of this kind
will be one of the characteristic features of the Regent’s Park and other
zoological gardens, or when an experimental station will be founded in
memory of Darwin.

§ There seems little chance of rendering horses immune to the bite of
the tsetse fly, but zebra hybrids may withstand it; those I have already
bred seem uncommonly hardy. Further, hybrids between zebras and
English or other mares may be found invaluable in various parts of the
Empire. I have one that looks as if it would by-and-by be well adapted
for a mountain battery.

TELEGONY AND REVERSION. 59

views held by Darwin, Spencer, Weismann, Romanes, and
others on the “ infection” theory.

Lord Morton’s object apparently was not to ascertain
whether there was such a thing as “infection of the germ,”
but simply to see whether it was possible to domesticate
the quagga, now, alas! extinct. In the letter addressed
to the President (Dr. Wollaston) of the Royal Society on
August 12th, 1820, Lord Morton says: “I obtained a
male, but being disappointed of a female [quagga] I tried
to breed from the male quagga and a young chestnut mare
of seven-eighths Arabian blood, and which had never been
bred from. The result was the production of a female
hybrid, now five years old, and bearing both in her form
and in her colour very decided indications of her mixed
origin. I subsequently parted with the seven-eighths
Arabian mare to Sir Gore Ouseley, who has bred from her
by a very fine black Arabian horse,... a two-year-old
filly and a year-old colt, which in their colour and in the
hair of their manes have a striking resemblance to the
quagga.”* It is further mentioned in the now famous
letter that the colt and filly were in some respects more
striped than either the quagga or the quagga hybrid,
and it is added that while the mane of the filly was
stiff, short, and erect, as in the quagga, that of the colt
arched upwards, as in the hybrid.

Notwithstanding these quagga or hybrid-like characters,
few biologists at the present moment admit that Lord
Morton’s chestnut mare was “infected” by the quagga.
Darwin, however, in 1875 seems to have believed the
chestnut mare had been “infected.” He says, ‘‘ These
colts [the colt and filly bred by Sir Gore Ouseley] were
partially dun-coloured, and were striped on the legs more
plainly than the real hybrid or even than the quagga. One
of the two colts had its neck and some other parts of its
body plainly marked with stripes. Stripes on the body,
not to mention those on the legs, are extremely rare—I
speak after having long attended to the subject—with

* «Phil. Trans.,’ 1821, p. 21. For complete letter see Appendix.

60 TELEGONY AND REVERSION.

horses of all kinds in Europe, and are almost unknown in
the case of Arabians. But what makes the case still
more striking is that in these colts the hair of the mane
resembled that of the quagga, being short, stiff, and up-
right. Hence there can be no doubt that the quagga
affected the character of the offspring subsequently begot
by the black Arabian horse.” *

In the same chapter Darwin, referring to a horse bred
by Lord Mostyn from a mare that had previously borne a
foal to a quagga, says, “This horse is dun with a dark
stripe down the back, faint stripes on the forehead between
the eyes, plain stripes on the inner side of the fore-legs,
and rather more faint ones on the hind legs with no
shoulder-stripe. The mane grows much lower on the fore-
head than in the horse, but not so low as in the quagga or
zebra. The hoofs are proportionally longer than in the
horse,—so much so that the farrier who first shod this
animal, and knew nothing of its origin, said, ‘Had I not
seen | was shoeing a horse I should have thought I was
shoeing a donkey.’” It is especially worthy of note that
Darwin favoured the view that Lord Morton’s mare had
been infected, notwithstanding the fact that he had bred
and described a colt which for some weeks after birth was
marked over the body, legs, and face by numerous narrow
stripes.t Many cases of supposed infection in birds, and
still more in domestic mammals, have been put on record,
but none of them are in my opinion so striking as the
two just mentioned.

One of the most industrious collectors of supposed cases
of telegony was Dr. Harvey of Aberdeen, who contributed
papers on this subject to the Monthly Journal of Medical
Science for the years 1849, 1850, and 1854, and published
in 1851 a pamphlet on ‘A Remarkable Effect of Cross-breed-
ing. Harvey eventually persuaded himself that there was
such a thing as “infection.” He believed he had finally
raised the tradition to the rank of a fact, and accordingly

* «Animals and Plants under Domestication,’ vol. i, p. 435, 1875.
+ Loc. cit., vol. i, p. 60.

TELEGONY AND REVERSION. 61

discussed at some length the possible methods by which
the “infection” was brought about.

Of quite recent writers, Herbert Spencer has felt most
satisfied as to the fact of telegony. In a series of papers
in the Contemporary Review,* in which telegony has prac-
tically been taken for granted, Spencer has especially con-
cerned himself with finding an explanation of the pheno-
menon. Spencer thinks that the evidence he submits by
“coming from those who have no theory to support, dis-
sipates all doubt,” and he endeavours, as will be further
explained below, to account for telegony by supposing that
germ-plasm from the embryo reaches and “infects” the
maturing ova through the tissues of the dam.

The late Mr. Romanes (whose telegony experiments were
abruptly cut short by his untimely and widely lamented
death), in a reply to Mr. Herbert Spencer says, ‘On the
present occasion space does not admit of giving special
instances, so I must ask it to be taken for granted that
my evidence is enough to prove the fact of a previous
sire asserting his influence on a subsequent progeny.” +t
Elsewhere,t on giving the upshot of an extensive corre-
spondence on the subject under consideration, Romanes
states that “the principal result is to show that the phe-
nomenon is of much less frequent occurrence than is gene-
rally supposed. Indeed, it is so rare that I doubt whether
it takes place in more than one or two per cent. of cases.”

Before stating the view Weismann holds as to “ infec-
tion” I perhaps ought to indicate what English breeders
think about the subject. This will be best accomplished
by the following quotations from two letters which appeared
in The Sportsman early in 1896. The writer of the letters
(the “Special Commissioner ” to The Sportsman) is, I under-
stand, one of the most influential men in racing circles in
England. In a letter dated January 3rd, 1896, the ‘ Special
Commissioner ”’ says, “‘ There would seem to be gentlemen

* Vol. lxiv.

+ Contemporary Review, April, 1893.
£ ‘An Examination of Weismannism,’ 1893, App. 2, p. 199.

62 'ELEGONY AND REVERSION.

who are as yet unaware that previous matings do un-
doubtedly in many cases exercise an influence on all the
subsequent stock of a mare or other female animal. Now
I should never have expected to find anyone disputing this
undoubted fact, and the only question appeared to be
whether the old theory, which ascribed it to the imagina-
tion of the mother or some equally unsatisfactory cause,
should not be replaced by the infinitely more sensible doc-
trie of saturation, which is thus defined by Mr. Bruce
Lowe :—‘ Briefly put, it means that with each mating and
bearing the dam absorbs some of the nature or actual
circulation of the yet unborn foal, until she eventually
becomes saturated with the sire’s nature or blood as the
case may be.* . . . I confess that this theory has always
appeared to me as a most reasonable one. As to the fuct
of sire influence which it professes to explain, I may
inform correspondents who are in any doubt about it that
it would not be difficult to furnish them with hundreds
or even thousands of instances.”’+ Ina subsequent letter
(January 22nd) the ‘Special Commissioner” says, “I
should as soon have expected anyone to boldly contend
that the earth is not round . . . as to deny the existence
of this influence,” 7. e. of the influence of the previous sire.
Another writer in the same paper says, “It is perfectly
surprising that anyone should doubt that saturation is an
important part of the theory of breeding. There would be
little difficulty in showing that it is not only a fact, but a
proven and most important factor.” This writer tells us
an experienced veterinary surgeon, who also raced, often
said to him, “It is of the greatest importance to mate your
mare the first time with a good horse; she will always
throw a bit towards him.”t Similar advice would be
given by the majority of veterinary surgeons if they hold
with the view that emanated some years ago from the
Principal of the Bombay Veterinary College. In an inte-

* Bruce Lowe, ‘ Breeding on the Figure System.’
t The Sportsman, January 3rd, 1896.
t Ibid., January 17th, 1896.

TELEGONY AND REVERSION. 63

resting paper on mules the Principal says:—“ An extra-
ordinary influence is exerted on the system of a mare by
becoming the mother of a mule, in so far as her progeny
in the future is liable to a taint indicated by asinine
characters cropping up. Thus no brood mare of high
value should be made to throw a mule—a fact well estab-
lished by the experiment made by Lord Morton of crossing
a mare of pure blood with a quagga.”’ *

It is, perhaps, not to be wondered at that in England,
where there has been hitherto in many quarters a dread
of scientific methods akin to that of the supernatural,
breeders have failed to distinguish between facts and
beliefs. In this case inquiry may justify the wide accept-
ance of the belief in question, but until the verification
has been effected it is not wise to allow the tradition to
overmuch influence practice, or to argue, as some believers
in telegony have done, that because the dam is infected the
sire must be infected also; that a Chillingham bull, e. g.,
which has been used for breeding with shorthorn cows
will, if returned to his own herd, infect it with shorthorn
peculiarities and idiosyncrasies. While many English
breeders have been, it may be, over-credulous, not a few
German breeders have long looked with suspicion on the
infection theory. Professor Kuhn, late head of the Prussian
Agricultural Station at Halle, Settegast, Nathusius, and
others familiar with scientific methods have, notwith-
standing an extensive experience in breeding and crossing,
never known a case of telegony. Hence, while some have
doubted its ever occurring, others are convinced there is
no such thing as telegony, that the female is neither “ in-
fected ” by the first male nor by subsequent mates to which
she bears offspring.

Weismann, who, as is well known, is not a believer in
the infection theory, wrote in 1893 as follows :—‘‘I must
say that to this day, and in spite of the additional cases
brought forward by Spencer and Romanes, I do not con-

* Mr. J. H. Steel, A.V.D., ‘Journ. of the Bombay Nat. Hist. Soc.,’
vol. v, 1890.

64. TELEGONY AND REVERSION.

sider telegony has been proved. I do not dispute the
possibility of telegony; I grant that the wide general
acceptance of the belief in the past has so impressed me
that I have always said that possibly it might be justifiable
and founded on fact. I should accept a case like that of
Lord Morton’s mare as satisfactory evidence if it were
quite certainly beyond doubt. But that is by no means
the case, as Settegast has abundantly proved... . The
attempt must be made to determine the truth by new
experiments. . . . According to scientific principles, only
the confirmation of the tradition by methodical investigation,
in this case by experiment, could raise telegony to the rank of
a fact.”* Not a few biologists and breeders agree with
Weismann in questioning the fact of telegony, in consider-
ing “infection”? as extremely improbable if not absolutely
impossible. Why, it may be asked, are many naturalists
now-a-days not satisfied with the evidence afforded by
Lord Morton’s case? Why does Weismann tell us he
inclines to Settegast’s view “that there is no such thing
as an ‘infection’ of this kind, and that all the instances
which have been recorded and discussed critically ...
are based upon a misconception?” + Why, while the belief
in infection forms an important part of the creed of breeders,
did Romanes and other scientific believers in telegony think
it occurred but rarely, in only one or two per cent. of cases f

When Lord Morton’s case is considered critically the
evidence in support of infection is found to consist chiefly
(1) in the colt and filly presenting quagga- or, to be more
accurate, zebra-like markings; and (2) in the filly having,
according to Lord Morton, a quagega-like mane while the
colt had a mane like the quagga hybrid. Weismann, fol-
lowing Settegast and others, if asked to account for the
stripes on the colt and filly, would reply by saying they were
due to reversion or atavism. This answer I need hardly
point out is based on the assumption that there is such a
thing as reversion, and on the further assumption that the

* Contemporary Review, vol. xiv.
+ ‘The Germ-plasm,’ p. 386.

'ELEGONY AND REVERSION. 65

ancestors of the horse of to-day were even more striped than
the recently extinguished quagga (Fig. 13). Granting rever-
sion, and granting also that the various breeds of horses have
descended from profusely striped ancestors, Weismann’s
answer would be quite legitimate. But some biologists,
who are not prepared to allow that reversion of this kind
ever occurs, would not admit the relevancy of Weismann’s
answer. If not adopting the “ infection” explanation

Fie. 13.

Lord Morton’s Quagga (after a drawing by Agasse).

they would probably say the stripes on the colt and filly
were an instance of excessive or discontinuous variation—
their resemblance to ancestral markings being a mere acci-
dental coincidence.

Although it is impossible to prove that reversion occurs
in horses, as it admittedly does in pigeons, I believe that
if the markings on Sir Gore Ouseley’s “ colts” were not
due to the dam having been influenced in some way by the

5)

TELEGONY AND REVERSION.

66

Cuopuory ‘snypy “Sang “jo “Koy “Suraverp s,asseSy wolg) “pNqsyy wssun% s,loy10J_ psory

FT “Old

67

TELEGONY AND REVERSION.

(‘aopuory ‘snqq
“Bing ‘Tfo9 ‘Aoy ‘Sarmvrp s,asseBy wor) “aepl s,aopopy prory wosy fayasng as0y arg fq paag Aqrz
S TOD “ANY SUraeAp s, V J W 8. CO}O]T prory wos

“aT “OTT

68 TELEGONY AND REVERSION.

quagea they resulted from reversion. I prefer the rever-
sion explanation, because it seems to me to be simpler and
more in accordance with established facts. I have fre-
quently seen numerous zebra- or quagga-like stripes not
only in foals but also in aged horses, stripes on the face
as well as on the shoulder, neck, body, and legs. Hence
the possibility of reversion may in the meantime be taken
or granted, and the further question asked, Were the
markings on the “ colts” sufficient in themselves to prove
that the Arabian mare had been infected by the quagga?
I think it must be admitted that the stripes taken by them-
selves are barely sufficient to prove intection. If the paint-
ings by Agasse (in the Royal College of Surgeons’ Museum,
Lincoln’s Inn Fields, Loudon) are accurate, Lord Morton’s
quagea-hybrid (Fig. 14) was but feebly striped. Agasse
shows three distinct but short stripes across the left shoulder,
four faint and still shorter stripes on the neck, ten cross-

”

stripes on the fore-leg—six of them between the knee and
the elbow—and nine cross-markings on the hind leg, five
of which le above the hock. When I first saw Agasse’s
drawing of the quagga-hybrid I was surprised at the
meagreness of the striping. In all my hybrids there are
more stripes than in their zebra sire, and the general, though
not universal, result of crossing zebra mares with asses and
horses has been the production of abundantly striped cff-
spring. Further, although there were no cross bars (Fig. 13)
on the legs of the quagga,* there were more stripes on the
legs of the hybrid than elsewhere. Hence in the case of
the hybrid at least we seem to have certain evidence of
reversion—reversion to the ancestors of the horse or the
quagga, or as Mr. Galton would perhaps put it, regression
to the ancestral mid-parent.t Ihave had in my possession
horses with more stripes than are represented by Agasse
in Lord Morton’s quagega-hybrid, and hence it would be

* Although, as far as I am aware, there are no stripes on the legs of the
quaggas preserved in museums, I understand quagea foals h
striped legs.

+ ‘Natural Inheritance,’ London, 1889.

ad sometimes

TELEGONY AND REVERSION, 69

difficult to prove that this hybrid was not indebted to its
ancestors on the female side of the house for all the stripes
it possessed.

In the filly—the second foal of Lord Morton’s mare—
faint stripes are shown by Agasse across the fore-leg
between the elbow and knee, and across the hind leg above
and below the hock. Onthe neck there are seven stripes,
and there are eight stripes across the body behind the
shoulder-stripe, which vary considerably in length (Fig. 15).
There are thus quite twice the number of stripes on the
neck and body of the filly that are shown in the hybrid, and,
unlike the quagga (Fig. 13), the filly has stripes on both the
fore and hind limbs. Inthe colt Agasse represents a broad
shoulder-band which looks as if it consisted of two or
more stripes. In front of this band there are several
{eight or nine) stripes on the neck, while behind the
shoulder-stripe there are others extending nearly to the
loins—twelve quite distinct and two doubtful. I noted
also five faint markings across the fore-leg above the knee,
and two equally obscure markings across the hind leg
above the hock. In the fourth foal of Lord Morton’s
uare (which, like the second and third, had for his sire Sir
Gore Ouseley’s black Arabian horse) I detected in Agasse’s
sketch eight stripes in all, three very faint stripes in front
of, and four behind, the shoulder-stripe.

Weismann points out in reference to the stripes on the
subsequent foals of Lord Morton’s mare that similar stripes
are “not very uncommon on purely bred foals, and ordi-
narily disappear as the animal grows older.” I have seen
eleven pairs of stripes on a Shetland foal, and Darwin, as
already stated, bred a foal marked by numerous narrow
stripes, some of them as tar back as the croup. Neverthe-
less I am not sure that Weismann, in saying that stripes
such as Agasse shows in the two-year-old colt are ‘‘ not very
uncommon on purely bied foals,” gives a sufficient and
final answer. While stripes at birth may be accounted
for in some cases by saying they are simple relics of
ancestral markings, it does not necessarily follow that they

70 TELEGONY AND REVERSION.

may be thus accounted for in all cases ; and notwithstanding
all the criticisms that have been made, it is quite possible
that had Lord Morton’s mare not borne a hybrid foal to a
quagga her offspring to the black Arabian horse might
have been absolutely devoid of stripes even as foals.

Darwin was abundantly familiar with the fact that
stripes now and again appear on the shoulder, legs, neck,
and face in horses in all parts of the world and of various
breeds and colours. Hence I imagine that, on coming to
the conclusion that the quagga had affected the character
of the subsequent offspring begot by the black Arabian
horse, he was not a little influenced by Lord Morton’s
description of the mane in the colt and filly. Undoubtedly
stripes together with an erect or nearly erect mane would
practically prove infection had taken place. This leads
me to consider the evidence afforded by the mane in the
Ouseley colts. Lord Morton, referring to the mane, says,
“That of the filly is short, stiff, and stands upright, and
Sir Gore Ouseley’s stud-groom alleged that it never was
otherwise ; that the mane of the colt is long, but so stitt
as to arch upwards and to hang clear of the sides of the
neck, in which circumstance it resembles the hybrid. This
is the more remarkable as the manes of the Arabian breed
hang lank, and closer to the neck than those of most
others.”

When some days ago I re-examined the oil-paintings
by Agasse of Lord Morton’s mare, her quagga-hybrid, and
her three foals to Sir Gore Ouseley’s black Arab horse, I
specially noticed, as was previously pointed out by Sette-
gast, that the mane of the filly (Fig. 15) was not represented
as short, stiff,and erect, while that of the colt was not shown
as arching upwards.* It is well known that the mane of

* I failed to ascertain the date of the paintings, but from the third pure.
bred foal forming one of the series it may, I think, be taken for cranted
that the sketches were made during the summer or autumn of 1821, v. e.
about a year after Lord Morton made his communication to the Royal
Society. Lord Morton’s mare, it may be mentioned, missed having a foal
in 1820. See Sir E. Home’s ‘Comp. Anat.,’ vol. iii, p. 18, 1823.

TELEGONY AND REVERSION. 71

the horse is easily altered, In one of my Arabs (Benazrek)
the mane hangs lank and close to the neck, but in another
(once a polo pony) the mane six months ago was short,
stiff, and upright, while now that it is longer it arches
upwards free from the neck; some months hence it will
doubtless hang lank and close to the neck. Sir Gore
Ouseley’s stud-groom alleged the filly’s mane had always
been short, stiff, and upright; but this, it seems to me, is
proving too much, and the point at issue is far too im-
portant to rest on an allegation of this kind.

The necessity of repeating the Morton-Ouseley experi-
ment with a well-striped zebra became still more evident
when I read in 1895 Mr. (afterwards Sir Everett)
Millais’ ‘Two Problems of Reproduction,’* in which he
states: “I may further adduce the fact that in a breed-
ing experience of nearly thirty years’ standing, during
which I have made all sorts of experiments with pure-
bred dams and wild sires, and returned them afterwards to
pure sires of their own breeds, I have never seen a case
of telegony, nor has my breeding stock suffered. I may
further adduce the fact that I have made over fifty
experiments for Professor Romanes to induce a case
of telegony in a variety of animals—dogs, ducks, hens,
pigeons, &c.,—and I have hopelessly failed, as has every
single experimenter who has tried to produce the phe-
nomenon.” +

The Hybrid “Romulus” and his Sire and Dam.

Having made the necessary arrangements, I purchased
in the spring of 1895 two female zebras, a number of
mares of different sizes, colours, and breeds, an Arab
horse, and later, a handsome Burchell’s zebra (Equus
burchelli).t For months no progress was made, and for

* “Our Dogs” Publishing Company, Manchester, 1895.

+ The late Sir Everett Millais, like Romanes, believed that telegony was
possible, but he thought it was “exceedingly rare, and therefore abnormal ”
(loc. cit., p. 20).

+ This zebra might be placed in Mr, Pocock’s sub-species Chapmani.
(See Pocock’s paper on “The Species of Zebras,” ‘Ann. and Mag. of

72 TELEGONY AND REVERSION.

a time my attempt to cross mares with a zebra stallion
seemed destined to fail. In course of time, however, some
of the difficulties were overcome, and on August 12th, 1896,
a zebra-horse-hybrid made its appearance. Since then
four other zebra hybrids have arrived, and more are
expected next summer (1898)—all by the same sire. A
photograph of the first hybrid (Romulus) with his dam
(Mulatto) was reproduced in the Field of September 19th,

Fic. 16.

Mulatto.

1896, and a short description of the sire, dam, and hybrid
was published in The Veterinarian for November of the
same year.

The Dam, Mulatto.—Mulatto (lent for the experiments
by Lord Arthur Cecil) belongs to a Western Highland
breed, is nearly black in colour, and just under 13 hands in
height (Fig. 16). This breed has long been under observa-

Nat. Hist.’ July, 1897); and Mr. Prdézak’s ‘Wild Horses of Africa,’
MS., The Library, University of Edinburgh,

BeseeiSemensernnen trance an

---Matopo.

74, TBRLEGONY AND REVERSION.

tion, and, except in 1848, no fresh blood has been recently
introduced into the Island of Rum section of the group, to
which Mulatto’s sire belonged.* Hence these ponies may be
looked upon as forming a remarkably pure breed, and
Mulatto may be considered an excellent substitute for Lord
Morton’s all but pure Arabian chestnut mare.t As to the
Rum pony foals, I have learned from Lord Arthur Cecil
that they are at birth frequently mouse-coloured with a
faint dorsal stripe. After the first year the “colts” are
dark brown or nearly black, with in most cases hazel-
coloured eyes, a thick long mane and forelock, a long heavy
tail, chestnuts on both fore and hind limbs, but little hair
atthe fetlock joints. There is no record of these foals having
been marked with shoulder-stripes, though there has been
occasionally for a time a cloudy patch over the shoulders ;
neither have stripes been noticed on the legs, neck, or
body. In support of the belief of the late Marquis of
Salisbury (who owned the Island of Rum) that these
ponies had Eastern blood in their veins, it may be men-
tioned that in various respects they approach the highest
type of horses that has probably ever existed—I mean, of
course, the high-caste Arabs. I need only add as to
Mulatto that Romulus was her first foal, that she is now
(1897) six years old, and that she is of an extremely gentle
disposition,—as unlike as possible the restless, excitable,
Inquisitive zebra with which she was first mated.t

Lhe Sire, Matopo.—The zebra sire (Matopo) presents
all the characteristic markings of a Burchell’s zebra (Figs.
17 and 18), and though under thirteen hands, he is a hand-
some fellow, always in excellent condition, with fairly good
shoulders, perfect legs and feet, and very fine action. The
hind quarters are well formed, the tail is set on more as in

* The well-bred black West Highland ponies are or were found chiefly
on the Inner and Outer Hebrides, which lie to the west and north-west of

the mainland of Scotland—the survivors of the Island of Rum herd Lord
Arthur Cecil had removed some time ago to Kent,

+ Mulatto, by producing an abundantly striped hybrid foal, has proved
herself well fitted for the experiment from at least one point of view.

< For further particulars as to the West Highland ponies see p. 6.

TELEGONY AND REVERSION. » ED

a horse than in an ass. The warts (chestnuts), only present
on the fore-legs, are large, smooth, and black, Oval in
form, they measure 8 in. by 2 in., and lie as in the ass as
nearly as possible at the middle of the forearm. In summer
the stripes are nearly black, while the intervening spaces
on the sides of the neck, body, and hind quarters are of a
cream-colour; elsewhere they are nearly white. In winter
brown hairs (over an inch in length on the body, but shorter
on the face) grow out from the dark bands, while equally
long white hairs grow out from the intermediate spaces.
As summer sets in the long brown and white hairs are
gradually shed, the summer coat consisting of hairs from
an eighth to three eighths of an inch in length. During
the summer of 1897, as in 1896, a few of the long hairs
persisted on the sides of the body.* The skin is dark
throughout, under the white hair the skin is of an iron
grey colour, elsewhere it is nearly black owing to the pig-
ment in the hair roots. The mane consists at each side of
black and white tufts of hair, which alternate with each
other ; sometimes a narrow light patch an inch or two in
length is introduced into the neck to admit of this alterna-
tion being fairly regular. The central part of the mane
consists of black hairs measuring from five to six inches in
length, except over the withers, where they are short, and
between and in front of the ears, where they are from three
to four inches in length; the black central hairs are always
longer than the white lateral tufts, the difference in length
being greatest in the front half of the mane. Both the dark
and light hairs of the mane are shed annually, and the light
tufts are the same colour summer and winter—not white in
winter and cream-coloured in summer, like the spaces in
the neck with which they are continuous. The mane

* 1t is worthy of note that during the present winter (1897-98) the
long brown hairs have not yet (February) appeared. This is doubtless
due to the extreme mildness of the season. In its native country the
winter coat is worn during our summer, This may account for some of
the long brown hairs persisting during the two previous seasons well into
the autumn.

76 TELEGONY AND REVERSION.

extends on to the forehead four inches beyond the occipital
crest, to end in hairs which project directly forwards im-
mediately above a tuft of hair,* quite two inches in length,
that grows upwards at one side of the mane from the
point where the lower frontal stripes meet. The ears, which
are wide and rounded at the tips but not very long (62
inches measured along the upper surface), are lined with
almost white hair, and have dark margins. When pro-
jected forwards the ears form with the mane three broad
bands, which like the stripes melt into grey by moonlight.

The upper part of the tail (about ten inches) is trans-
versely striped, and one third of the striped part is covered
with short hair similar to that onthe hind quarters. From
the terminal part of the tail long dark persistent hairs
grow out, which reach to within a foot of the ground,
The intermediate part of the tail bears hairs which are
shed annually. These hairs vary in length from two to
eight inches; some are black, while others are white. In
the autumn some of these hairs form a crest continuous
with the dorsal band, while others project outwards to
form two lateral fringes. I need only mention further, as
to the colour of the hair, that though the muzzle looks
black in some hghts it looks grey in others. This is due
to the fact that the all but black skin is only sparsely
covered by very short hight hairs. Above each nostril the
hair is of a brownish colour. In the ill-defined “ nostril
patches” several of the facial stripes terminate. Between
the dark brown “ nostril patches ” the hair is almost black ;
in the Somali zebra, it may be mentioned, the muzzle some-
times in colour resembles that of a typical Exmoor pony
(is, in fact, “ mealy-coloured ”’), while the nostril patches
are of a bright tan colour.

In Matopo, asin most of the Burchell zebras, the stripes
on the forehead have a somewhat lozenge-shaped arrange-

* T shall speak of this tuft of hair as the frontal tuft; a similar but
usually shorter tuft is found in the horse under the forelock. The forelock,
which is sometimes considered a special growth, consists simply of the
front part of the mane.

TELEGONY AND REVERSION. we

ment (Fig. 19). Two stripes, one starting above each eye,
meet in the middle line near the end of the mane to form an
acutely pointed arch—the orbitalarch. Above this pointed ©
arch are four rounded arches; the lowest ends in the
frontal tuft already alluded to, the others extend into the

Fie. 19. Fic. 20.

Matopo. Romulus.

mane. Within the orbital arch are two distinct and still
more acutely pointed arches. The limbs (each being double,
as is also the case with the orbital arch*) of the outer of

* From the limbs of these arches being double it may be inferred
that Matopo’s aneestors had at least double the number of frontal arches.

78 TELEGONY AND REVERSION,

these arches curve inwards on a level with the eyes, and
run down to end in or near the nostril patches. The limbs
of the inner arch bifurcate about the level of the eyes, and
also proceed towards the muzzle, one of them again forking
on the way. Within the innermost acutely pointed arch
are two nearly vertical stripes; both of these split where
they blend with the arch above, while the right one again
splits before it reaches the muzzle below. The three

Fie. 21.

Somali Zebra (L. grevy/).

pointed arches and the first rounded arch meet in the
middle line, and from their junction the long hairs grow
out which form what I have spoken of as the frontal tuft.
I have described thus fully the stripes on the front of
the face of Matopo that a comparison may be afterwards
made between his acutely pointed frontal arches and the
numerous rounded arches in the hybrid offspring, Romulus

TELEGONY AND REVERSION. 79

(Fig. 20). To admit of further comparison with the hybrids
it is necessary that I should also describe at some length
the stripes on the body of Matopo. Not only are no two
individuals of any given species or variety of zebras alike
in their marking, but in no single individual is the pattern
the same on both sides.* But notwithstanding the varia-

Fig. 22.

“has

Skin, Somali Zebra.

tion in individual zebras, and the extreme cases of varia-
tion within the same species, it is possible to recognise

* As far as I can learn, want of symmetry in the coloration of plants
and animals is comparatively common. On the other hand, in plants and
probably also in animals, a point is eventually reached in the difference of
the two sides which is prejudicial to the life of the variety or species.
Were not this the case, wild animals would doubtless be as asymmetrical
in their coloration as our artificially protected domestic animals. While

_intercrossing makes for asymmetry, inbreeding seems to lead to symmetry
“in the markings. Mr. Prdzak tells me the Craddock, an inbred race of
‘mountain zebras, are remarkably symmetrical in their markings.

‘4yny [ByVOA “Zy “yoqud Lysoyy ‘d'e -sadtaqs Jeotadao ysxy Jo WoluN qe SumuSeq puvg peawoa “g' A “pueq pessog ‘q'q ‘ediays
VY JMOL 10 PUG “QS yPT ‘odiys Yury aqeipomsaoyuz gy ‘saduyqs onbyqo sayy av siyy Jo quoay u—odrys yuey yoy “gyyH ‘sediys
MOMIA “SA ‘adiays PeuouNY YS A caduys aopmnoyg -g'g ‘oduays peotasao ys “SOT “(2unmdnya *a “apoyaing 7) doy Wi sadiys*yo weisei(]

"yng [equony f° “qoqed [uysony ‘d'w ‘purge A “g™A “pug [esIog ‘gq’ ‘sadrays yexoway JMO] “gQyy'T ‘adiys [etouoy soddg ‘gag
radiays dnorg ‘gg ‘sadiys jexawng ‘gE cadtays aapqnoyg “gg -adiays yeotasgo II “SOL “(24aa08 7) eagoez, yewog & ut sodiays jo weiSerq

82 TELEGONY AND REVERSION.

a general plan in their marking. I consider the Somali
zebra (Fig. 21) the most primitive of all the zebras. This
conclusion has been arrived at mainly from a compara-
tive study of the markings of zebras. I have examined a
number of skins from Somaliland (one of which was a
well-preserved and quite complete foetal skin), numerous
Burchell’s zebra skins, several skins of the mountain
zebra, and the Amsterdam, Leyden, London, and Edin-
burgh quaggas.

The chief difficulty in dealing with zebras is to find
possible points of comparison in the marking of the dif-
ferent species and varieties. In all the zebras there is,
however, one very distinctive stripe, viz. the stripe which
typically extends downwards from the withers to bifurcate
somewhere above the level of the shoulder-joint; one
division proceeding forwards across the shoulder-joint, the
other backwards behind the elbow.* This characteristic
stripe I shall speak of as the shoulder stripe (Figs. 17, 18,
and 23, 8.8.). Occupying the triangular space formed by
the two limbs of the shoulder stripe and the transverse
band at the base of the forearm, we find in the Somali
zebrat some ten narrow arches (the humeral stripes) (Fig.
24, H.S.), the upper ones pointed, the lower ones rounded.
In Matopo (Fig. 23) only portions of three humeral stripes
cau be made out, but a Burchell’s zebra filly (Fig. 25)
from the Transvaal had at least seven. Between the
shoulder stripe and the occipital crest there are in Matopo
twelve stripes continuous with black bands in the mane
(Fig. 23). In the Transvaal filly there are twelve stripes
on the right side and ten on the left, but as there is a
“shadow” or indistinct stripe (Fig. 25) running down

* In Matopo neither of the divisions of the shoulder stripe reach the
ventral band; this band usually begins at the junction of the two stripes
lying immediately in front of the shoulder stripes. Mr. Prazak, I think
rightly, looks upon the shoulder stripe even when consisting of a single
band as made up of two stripes (‘ Wild Horses of Africa’). ;

+ By the Somali zebra I invariably mean the Somaliland variety of
Grevy’s zebra, not the typical Grevy’s zebra (Z. grevyi, Oust.) of Shoa.

TELEGONY AND REVERSION. 83

the majority of the light bands in this filly, there were
probably at least twenty-four cervical stripes between the
occipital crest and the shoulder stripe in the ancestors of
the zebras. In the Somali zebra there are sometimes
fourteen cervical stripes extending into the mane, but
judging by the width of some of them a considerable
amount of blending has evidently taken place.

A careful examination of the hind quarters of the
Somali zebra reveals the fact that there is a stripe which

Fie, 25.

Young Burchell’s Zebra with ‘‘ shadow stripes.”

has nearly the same relation to the hip-joint as the shoulder
stripe has to the shoulder-joint. This, the croup stripe
(Fig. 24, C.8.) (which typically consists of two stripes), also
when single bifurcates ; one limb running backwards across
the hind quarters, the other forwards to unite with the
first of a series of distinct stripes which arch across the
hind quarters, and may be known as the femoral stripes

84. TELEGONY AND REVERSION,

(Fig. 24, F.S.). Between the shoulder and croup stripes
in the skin figured (Fig. 24) there are twenty-five stripes
running at nearly right angles to the dorsal stripe. But
as four of these are more or less forked at their origin, the
twenty-five probably represent at least twenty-nine vertical

Fic. 26.

Mountain Zebra (2. zebru).

stripes. Hence it may be inferred that in stil] more primi-
tive zebras there were numerous narrow not very well de-
fined stripes running vertically across the body between the
shoulder and croup stripes. As in the case of the shoulder
stripe, several arches (modified femoral stripes, Fig. 24,

TELEGONY AND REVERSION. 85

U.F.S.) occupy the space between the two divisions of the
croup stripe. The anterior limbs of these arches usually
blend or all but blend with the first of the complete femoral
stripes (Fig. 24, 1.F.S.). Between the croup stripe and the
root of the tail there are at least twenty narrow stripes
which arch backwards. These stripes begin some distance
from the dorsal band,* and form with the corresponding
stripes of the opposite side a series of arches which
diminish in size from before backwards (Fig. 22). Trans-
verse markings extend across the tail to near where the
long hairs of the tip spring; in some cases not a few of the
caudal markings blend to form two narrow bands—one at
each side of the tail.

It is difficult if not impossible to identify a croup stripe
in the mountain zebra (H. zebra, Fig. 26), or in any of
the Burchell zebras. Nevertheless I shall endeavour to
show that a certain amount of resemblance exists between
the stripes of the Somali and all the other zebras. In
Matopo a pronounced band may be traced from the root of
the tail (with the stripes of which it is in line) forwards
over the external point of the ilium (haunch) across the
flank, to curve downwards and inwards and finally end
in the ventral band. This, which may be known as the
caudal or great flank stripe (Fig. 28, G.F.S.), is present in
all the Burchell skins I have examined. With the excep-
tion of the Burchell zebra proper, there are in all the
Burchell varieties and sub-species I have seen two other
well-marked flank stripes. The lowest of these (Fig. 23,
L.F.S.) is intimately related to the stifle (knee proper), at
or near which it frequently bifurcates, one division, usually
slender, running down in front of the stifle, the other or
main division (Fig. 18) extending forwards and inwards to-
wards the ventral band. This may be known as the stifle or

* In some of the Somali zebras the narrow transverse (croup) stripes
are at their origin only a short distance from the dorsal band; in others a
fairly wide light space intervenes between the croup stripes and this band.
But when the croup stripes all but reach the dorsal band, they are for an
inch or two only faintly coloured.

86 TELEGONY AND REVERSION.

lower flank stripe. The other flank stripe (Fig. 23, LF.S.),
which lies between the caudal and stifle stripes, may be
known as the intermediate flank stripe.* In Matopo the
third flank stripe stops short of the ventral band, while in
the true Burchell zebra (Fig. 27) the third flank stripe 1s
at the best feebly developed. Between the great flank
stripe and the vertical stripes there are in the crawshayt
zebras a number of oblique stripes, some of which reach the

Fie. 27.

A Typical Burchell’s Zebra (2. burchelli).

ventral band. In the common zebra, the stripe (Figs. 26
and 28) which forms one of the handles of the “gridiron” t
I look upon as corresponding to the caudal or great flank
stripe of Matopo; it has the same relation to the root of

* In‘some zebras one or more of the flank stripes may bifurcate or unite
with one of the adjacent stripes as it proceeds towards the ventral band.

+ The stripes across the croup and rump, together with the two great
flank stripes, may be said to forma “ gridiron” with two long handles.

*(ahpysansa “A “19 9YILNG ‘W) v1Ig97, s keysmvig “TYG *(n.1gaz ‘T) rAgay, TTeyUNOyy “UIyg

88 ELEGONY AND REVERSION.

the tail, and is the third stripe in front of the stifle. Is it
possible to detect in the Somali zebra stripes corresponding
to the three flank stripes in the common and Burchell
zebras? I look upon the femoral stripe, which in the
Somali zebra is intimately related to the stifle, as the
equivalent of one of the oblique stripes lying between the
vertical and flank in the Burchell zebras. This stripe,
which in the Somali zebra forms a frame for the insertion
of a number of transverse stripes, in all probability also
corresponds to one of the long curved handles into which
is inserted the transverse base of the “gridiron” of the
mountain zebra. That there is some relation between the
femoral stripes in the Somali zebra and the oblique and
flank stripes of the other zebras will be more evident when
the croup and flank and femoral stripes in zebra hybrids
are taken into consideration.

From the stripes in the mountain and Crawshay zebras
(Figs. 28 and 29) it is comparatively easy to derive the
varied patterns which obtain in the Chapman and Burchell
zebras. Between the lower part of the stripe which forms
the frame of the

(a3 »

eridiron ” in the mountain zebra (Fig.
28), and the shoulder stripe, there are in the skins I have
seen from nine to ten nearly vertical stripes crossing the
sides, the majority of which in some cases reach, or all
but reach, the ventral band (Fig. 30); while in the Somali
zebra at the same level there are from eighteen to twenty
stripes, some of which after a short break also reach the

ventral band.* As the number of stripes in zebras is

* Pocock, in referring to the common zebra (Z. zebra), says, ‘“ Except
for the longitudinal ventral band the belly is white, the flank stripes
stopping short of the belly as in the quagga, Burchell’s zebra, and Grevy’s
zebra.” In the common zebra I saw Jast March in the Amsterdam Zoologi-
cal Gardens, stripes extended right across the belly, and in the foal (now,
1898, in the Zoological Gardens, London) the long broad ventral fringe of
hair was partially striped like the mane. This striation of the ventral
fringe (which has not, as far as I am aware, been ever described) is quite
evident ina photograph (Fig. 30) for which I am indebted to the Director,
Dr. C. Kerbert. In the Somali zebra some of the vertical stripes may
reach the ventral band. As they cross the belly they get lighter and

TELEGONY AND REVERSION. 89

evidently sometimes reduced either by two or more blending,
or by alternate stripes first forming shadow stripes and then
disappearing, the nine to ten vertical body stripes in the
common zebra may be equivalent to the eighteen to twenty
stripes in the Somali zebra. In the Burchell zebras, when
the shadow stripes (Fig. 25) are included, there are often
eleven vertical stripes* between the shoulder stripe and the
great flank stripe, i.e. the stripe corresponding to one of

Fie. 30.

Mountain Zebra and Foal (Amsterdam Zoological Gardens).

the handles of the gridiron in the common zebra. Hence
the only essential difference between the Burchell and the

lighter, until they are almost invisible; but when within two or three
inches of the ventral baud they become nearly as distinct as they are on
the sides of the body.

* In Matopo four vertical stripes reach the ventral band (Fig. 23),
while in the Transvaal filly (Fig. 25) three stripes on one side and two
on the other reach the ventral band.

90 'RLEGONY AND REVERSION.

common zebra is that in the latter the great flank stripe
has numerous cross-bars extending from it towards the
dorsal band. This gap between the mountain and Burchell’s
zebra is (as far as the markings are concerned) bridged
over by members of Crawshay’s group of zebras. Hence,
as already indicated, it appears (1) that the arrangement of
the stripes over the flank and hind quarters in Matopo has
been arrived at by the femoral stripes of the Somali zebra
arching upwards and forwards so as to entirely obliterate
the numerous narrow stripes across the croup and rump ;
(2) that a less complete migration of the femoral stripes
would result in the plan which prevails in the Crawshay
type of zebras (Fig. 29); and (3) that such a “gridiron”
as exists in the mountain zebra would almost at once result
from the shunting upwards of the posterior end of the
first complete femoral stripe in the Somali zebra. In other
words it appears that the plan of marking in the common
zebra might be easily derived by a modification of the
stripes in the Somali zebra, and that by further modi-
fications in the same direction the various patterns pre-
sented by the stripes in the Crawshayt, Chapmani, and
Burchelli types of zebras might also be obtained. I do not
wish it to be inferred that the Burchell zebras have been
derived from the common zebras, but simply that the
ancestors of the Burchell zebras once upon a time more or
less resembled in their markings the common zebra of
to-day, and that their still more remote ancestors probably
resembled in their markings the Somali zebra.

It need only be mentioned further as to Matopo, that
below the knee and hock the stripes are faint; that while
the front part of the pastern is white, the back part with
the exception of a mesially placed white triangular space is
decorated with very narrow dark brown stripes ; that there
are no hairs at the fetlock; that the chestnut (wart) on
the fore-leg—the only one present —while relatively much
larger than in the horse, is smooth and not raised above
the general level of the skin; that the hairs (vibrissa)
about the muzzle are longer and more numerous than in

Fie. 31.

14 4

ra,

Romulus (seven days old) and his dam, Mulatto.

Fie. 32.

es j
Romulus: twenty-seven days 0

d.

g2 VELEGONY AND REVERSION.

well-bred horses; and that only the five vertical stripes
behind the shoulder stripe blend with the dorsal band,
which, as in many zebras, expands slightly as it crosses
the croup.

Romulus —In Romulus, and in my other hybrid foals,
there are numerous stripes, but, as it happens, the plan of
the striping is in all of them quite unlike that of their sire
Matopo. This will be at once evident if the photographs
of Romulus (Figs. 31, 32, and 33) are compared with those
of his sire (Figs. 17 and 18). In Romulus (a year old on the
12th of August, 1897) the stripes on the forehead (Fig. 33)

Fic. 33.

Romulus : twenty-seven days old.

form a series of rounded instead of, as in his sire, pointed
arches (Fig. 19). In two of this year’s hybrids there are
similar arches across the forehead, but in the others the
pattern of the frontal stripes is somewhat different.
Romulus, in having rounded instead of pointed frontal

5
«

35.

Fic.

Crawshay’s Zebra.

Somali Zebra.

94 TELEGONY AND REVERSION.

arches, agrees with the Somali and Crawshay’s zebras
(Figs. 34 and 35). I have photographs showing the

markings on the face in five Somali zebras. No two are
alike, but in no case do the arches form acute angles, as in
Matopo (Fig. 19). In all the hybrids the stripes on the
forehead are more numerous* and consequently narrower
than in the Somali zebra.

In the striping of the neck, body, hind quarters, and lees
Romulus also resembles the Somali zebra far more than his
sire. In the case of Matopo there are twelve stripes which
extend into the mane between the occipital crest and the
shoulder stripe; in Romulus there are twenty-four stripes
in the same position. In the Somal zebra there are, on
an average, fourteen cervical stripes ; but evidently in this
zebra, as already mentioned, a certain amount of blending
of the cervical stripes has taken place. In Gray’s figure
of Burchell’s zebra, shadow stripes are represented in
front of as well as behind the shoulder stripe.t Notwith-
standing Gray’s figure I have heard doubts expressed as
to shadow stripes being present on the neck ot zebras.t
There is, however, no room for doubt on this point. In

* In Romulus there are fourteen narrow dark brown curved frontal
lines, with equally narrow pale lines between them.

+ ‘Zool. Journ,’ pl. iv, July, 1825.

t The danger in dealing with zebras is coming to conclusions from the
examination of any given collection of skins or specimens. Conclusions
arrived at to-day often stand in need of altering to-morrow, so great and
remarkable is the range of variation in the stripes, more especially in what
may be known as the Burchell group of zebras. Though familiar enough
with the variations in the markings of our domestic animals—which for
many generations have been removed from the influence of natural selec-
tion—we are hardly prepared to tind a wide range of variation in the
colour and marking of zebras living in a wild state in comparatively
limited areas. That in the case of the Burchell group of zebras (7. e. the
Crawshayi, Chapmani, and Burchelli zebras) there 1s a wide range of varia-
tion in the arrangement, colour, extent, and relations of the stripes, in the
mane and tail, and in the form of the head, neck, and hoofs, will be
abundantly evident if an attempt is made to classify them. A satisfactory
classification will not be possible until a large number of skins are available,
the district to which each skin belongs being in each case specified.

TELEGONY AND REVERSION. 95

my two zebra mares there were distinct shadow stripes on
the neck, and I have before me a photograph* of a zebra
in the Dublin Zoological Gardens showing four very dis-
tinct shadow stripes on the left side of the neck. In one
of my mares, which I understand was captured in the
Transvaal when a few weeks old, there were ten shadow
stripes on the left side of the neck (Fig. 25). These shadow
stripes, together with the twelve almost black stripes, made
twenty-two cervical stripes in all. On the right side there
were, in this mare, eight shadow stripes, which with ten
ordinary stripes made in all eighteen—a difference in the
two sides of four stripes. Evidently even the Burchell
zebras have had at one time a considerable number of dis-
tinct cervical stripes; and Romulus in having twenty-four
cervical stripes, if he does not reproduce an ancestral plan,
in all probability approaches nearer to it than his sire
Matopo. Between the shoulder stripe and the root of the
tail there are, as already indicated, in the Somali zebra
over forty stripes running outwards at each side at nearly
right angles to the dorsal band. In Romulus forty-three
stripes or portions of stripes may be made out between
the shoulder stripe and the root of the tail: in the
common zebra, notwithstanding its gridiron arrangement,
there are under thirty stripes. The first ten of these
stripes in Romulus seem to take the place of the five broad
nearly vertical stripes in Matopo. The stripes beyond the
tenth are at first narrow and indistinct, while over the
loins and croup they were at birth mainly made up of rows
of spots. Now that Romulus is a year old many of the
spots over the rump have united to form somewhat zigzag
stripes.t The majority of the stripes over the rump run
at nearly right angles to the dorsal band, but as the root
of the tail is reached some’ of them bend backwards, and

* Tam indebted to Professor D. J. Cunningham, F.R.S., of Dublin, for
this photograph.

+ ‘This, I think, proves that at least the transverse stripes over the
croup and rump, in the Somali and common zebras, have been formed by the
running together of rows of spots.

96 TELEGONY AND REVERSION.

thus very closely agree with the narrow recurved stripes in
the Somali zebra. In two of this year’s hybrids the rump
is less marked than in Romulus, while in one there has
been from the first all but complete narrow wavy lines in
place of the spots originally present in Romulus.
Although the arches within the two limbs of the shoulder
stripe are in Romulus almost as indistinct as were the
markings in this region in the quagga, they in a favorable
light are seen to be seven in number, t. e. aS numerous as
in the Transvaal filly (Fig. 25). Below the elbow, however,
the transverse markings are relatively broader and more
pronounced than in Matopo. On the outside of the leg
eighteen stripes can now he counted, while there are
seventeen on the inside. The spaces between the stripes
are of a dark mouse-colour from the elbow to immediately
below the knee, but they get gradually darker as the hoof
is reached, until it becomes almost impossible to detect
them. The inside of the leg is lighter than the outside,
the upper part of the forearm being of a drab colour on
its immer aspect. ‘The oblique and flank stripes are not
very well defined in Romulus. There is, however, a stripe
which seems to correspond to the great flank stripe in his
sire, though in its position it more closely agrees with the
first complete femoral stripe in the Somali zebra. This,
the third in front of the stifle, extends upwards to arch
across the upper end of the flank feather,* to lose itself
amongst the spots over the hind quarters. The second
(intermediate) Hank stripe runs obliquely across the feather,
expanding considerably near where the feather bapins.
After a considerable interruption this stripe, as Fig, 32
shows, agaiu appears as a narrow tapering band running
parallel to a more distinct stifle stripe lying at a lower
level. Now (1898) by the blending of spots the inter-
mediate stripe is more complete on the left side than at

* I propose to call the “swirl” or hair-shed that usually extends in
the horse between the stifle and the point of the ilium the flank feather.
A corresponding but shorter swirl, which I have occasionally seen extend-
ing upwards from near the elbow, may be known as the elbow feather.

TELEGONY AND REVERSION. 97

birth, while on the right side a number of spots have
recently blended to form a continuation of the upper flank
stripe. It thus appears that longitudinal as well as trans-
verse stripes may originate from the blending of spots.
The stifle stripe appears to begin at the bottom of the
flank feather. It then runs for some distance parallel to
the middle flank stripe, and after a short interruption
crosses the hind quarters as a well-marked band, to end
some distance below the root of the tail. The three flank
stripes, while differing in their position from the flank
stripes in Matopo, agree fairly closely with stripes in the
Somali zebra.

In front of the flank stripes are three oblique stripes
which, beginning on a level with the stifle, run upwards
parallel with the flank stripes to lose themselves amongst
the spots and indistinct narrow bands over the loins and
croup. Similar oblique stripes occur in some of the craw-
shayt type of zebras. In the space bounded in front by
the last vertical stripe, above by the dorsal band and below
by portions of the oblique and flank stripes, are numerous
nearly transverse stripes and rows of spots. The part of
this space in front of the croup is mainly occupied by in-
distinct narrow stripes, over the croup proper there are
interrupted more or less zigzag stripes, behind these nu-
merous spots. Round the root of the tail an attempt has
been made to form a series of semicircular lines (Fig. 11)
such as occur in the Somali zebra (Fig. 24). The “ grid-
iron” of Romulus thus agrees more closely with the
markings over the loins, croup, and hind quarters of the
Somali (Z. grevyt) than with those over the corresponding
parts of the mountain zebra (EH. zebra).

In describing the flank stripes in the hybrid I mentioned
they crossed the flank feather. In horses this swirl or
feather usually extends from near the level of the stifle to
near the point of the ilium or haunch-bone, while in asses
it is short, and usually nearly circular in form. In Matopo
there is no swirl formed by the hair in the region of the
flank, nevertheless there is a fairly long feather in my

7

98 TELEGONY AND REVERSION.

zebra hybrids. In Romulus it begins about four inches
above the level of the stifle, and extends relatively as high
as in the horse.* Between the lower flank stripe and the
hock stripe—the stripe which typically bifurcates as it
crosses the hock—there are ten distinct transverse bands,
between some of which fairly distinct shadow stripes may
be seen. Altogether it is possible to identify thirteen
stripes above the hock when the three flank stripes are in-
cluded. Below the hock the stripes are now (1898) rather
obscure, owing to the darkening of the intermediate spaces.
It is, however, possible to make out some thirteen stripes
on the outside of the leg below the hock. The inside of
the leg above the hock is of a drab or mouse-colour.
Within six inches of the stifle there is a straight stripe
running across the leg, and between this line and the hock
eight other stripes are present. While the outside of the
hind shank in Romulus has as many stripes as in his sire,
the inside is distinctly less striped; but, on the other hand,
the pastern and fetlock are much darker.

In Romulus there are only chestnuts on the fore-legs,
but in Remus—a bay Irish mare’s hybrid—there are chest-
nuts on both fore and hind legs, and in a Clydesdale’s hybrid
there is a small chestnut on one hind leg. In all my
hybrids, as in their sire, there are ergots at the fetlocks, but
only in two of the hybrids is there a distinct tuft of hair at
the fetlock. The mane in Romulus agrees with that of his
sire, except that many of the central hairs reach, before
they are shed, a length of eight or nine inches, and the
difference between the colour of the lateral tufts is not pro-
nounced. In Matopo the mane extends as far as the frontal
tuft, but in Romulus there is a gap of about half an inch
between the tuft and the mane. From the terminal part
of the tail, which is relatively longer than in the horse, a
bunch of long persistent hairs grow ; but from the greater
part of the tail the hair was shed during last winter, and
developed again during the spring.

* The flank swirl being quite small or absent in the ass, it is not surprising
to find that in a zebra-ass hybrid the feather or swirl is wanting, -

TELEGONY AND REVERSION. 99

In the Burchell zebras the eyes are less prominent than
in the horse. This is partly due to a slight insinking of
the eyeball and the absence of a prominent supra-orbital
ridge. In the hybrids the eyes may be said to unite the
characters of both parents. The lower eyelid instead of
inclining inwards as in the zebra is nearly vertical in
position, while the supra-orbital ridge is more prominent.
The upper eyelashes are, however, peculiar, and the upper
eyelid never seems to be raised as high as in the horse—
only the lower half of the eyeballis asarule exposed. The
upper eyelashes in all the hybrids, but especially in
Romulus and the very zebra-like Irish mare’s hybrid Remus,
are long and curved, so that even when the upper ld is
quite raised the long hairs arch downwards in front of the
eye. In my Arabs and in Matopo the upper eyelashes are
comparatively short, and when the lid is raised they pro-
ject almost directly outwards. In Matopo under the lower
eyelid the skin is coloured so as to resemble a fringe ;
similar marks are found in zebra hybrids, especially in
zebra-ass hybrids. The nostrils in Romulus and the
other hybrids are zebra-like, narrow, short, and almost oval
in form, and not deeply notched as in the horse at the
upper angle ; and the rounded outer margin of the nostril
projects freely outwards as in zebras and asses.

It thus appears that hybrids obtained by crossing dif-
ferent breeds of mares with a Burchell’s zebra stallion
differ in many respects from both their respective parents,
and yet, except in a few points, they can hardly be said
to occupy an intermediate position, to resemble the ideal
“ mid-parent ” that presumably combines the characters
of the two immediate ancestors. This is true not only
of their colour, but also of their make, habits, and dis-
position. They differ from their respective dams in being
elaborately striped, they differ from their common sire in
the number and disposition of the stripes. But what is
perhaps most remarkable is that, while differing from all the
Burchell zebras in the number and arrangement of their
stripes, all the hybrids either closely agree with the Somali

100 'ELEGONY AND REVERSION.

zebra or present what I consider a simpler and more
primitive arrangement, as, ¢. g., having twenty-four bands
in the neck, and in some cases having rows of spots
instead of transverse stripes in the region of the rump.
The hybrids may be said to take after their sire in their
nostrils, their hoofs, and to a less extent their chestnuts,
and in the males having two teats.* They may be said to
be intermediate in their make as a whole, but especially in
their ears, eyes, neck, withers, and hind quarters, and in
their mane and tail. In having a somewhat long head they
agree with the Somali zebra, but in having long curved eye-
lashes they are, as far as I am aware, unlike the majority
of both horses and zebras. In the dorsal band being
bounded along its whole length on each side by a narrow
yellow band, they differ from their sire, and again approach
the Somali zebra, in which there is a light space at each
side of the dorsal band for more than half its length.

Were the Ancestors of the Horse Striped ?

The fact that all the five hybrids differ in their mark-
ings very decidedly from their sire, while they in many
respects suggest the Somali zebra, demands an explana-
tion. Darwin seems to have been not only impressed
with the difference between hybrids and their immediate
ancestors, but also with their striking resemblance to
known or supposed remote ancestors.t He accounted for
this resemblance by saying crossing had led to reversion.
As the question of reversion is of the utmost importance
in considering supposed cases of telegony, it will be
necessary to deal with it at some length. There is, however,
a prior if not equally important question, viz., Have all

* Foetal colts have frequently, if not always, distinct rudiments of teats
up to about the sixth month. Relatively large teats are usually present
in the jackass and in male mules.

+ Mr. Francis Galton has long recognised that hybrids differ from their
immediate ancestors. He quite recently pointed out that “the offspring
of two diverse parents do not necessarily assume an intermediate form.”
—WNature, Oct. 21st, 1897, p. 599.

TELEGONY AND REVERSION. 101

our breeds of horses—Arabs, Exmoors, Clydesdales, &c.—
descended from striped ancestors, from hog-maned an-
cestors, elaborately decorated with bands on the face,
neck, body, and legs, after the fashion of one or other of
the “gaily painted zebras?” Evidently it is desirable to
consider this question before dealing with the reversion
hypothesis.

What evidence is there in favour of the view so generally
held that the ancestors of the horse were striped? Over
four thousand separate books have been published or
subjects appertaining to the horse, and though many of
these works devote a chapter to the horse of antiquity, I
believe I am right in saying that they afford no evidence
of a horse striped after the manner of a zebra or quagga
having existed during the historic period. What of the
prehistoric period? Every one knows that the paleolithic
cave-dwellers, instead of devoting much time to polishing
their implements, after the fashion of their neolithic suc-
cessors, spent some of their leisure in delineating on bone,
slate, and other permanent materials the beasts of the chase
—amonegst others the mammoth, reindeer, and horse. Now
although these paleolithic men lived many thousands of
years ago, they were evidently accurate observers. A sketch,
e.g., of a reindeer fight on a piece of slate is most spirited,
while that of a mammoth on a piece of ivory (found in the
Madelaine cave) is strikingly accurate. But what of the
horses? That the Troglodyte artist was abundantly familiar
with the horse will be evident. when I mention that near
Solutré, in the neighbourhood of Macon, to the north of
Lyons, there are the remains of thousands of horses which
had undoubtedly served as food during a considerable period
for a fairly large settlement of primeval men. The bones
of the horse are mingled with—to mention only ungulates
—those of the mammoth, Canadian deer, primeval ox, and
the saiga-antelope. The majority of the bones are broken,
the long ones having been split for the sake of the marrow.
Do any of the sketches, made it may be thirty thousand
years ago, throw any light on the striping of the horse?

102 'ELEGONY AND REVERSION.

Some think they do. ‘They certainly give evidence of
remarkable powers of observation; the legs, e. g., are
almost as accurately placed as in a Muybridge photograph.
Yet, notwithstanding a number of suggestive lines, these
primeval sketches can hardly be said to help us in answer-
ing the question, Were the ancestors of our various breeds
of horses striped? Though nothing definite can be learned
from either historic or prehistoric records, there may be
other available evidence. Every one knows that stripes
are not by any means uncommon, more especially in dun-
coloured Norwegian and Kattiawar ponies. Are these
markings vestiges of a striped coat, as complete, it may be,
as that of the quagga, or are they feeble attempts on the
part of some recent horses to mimic the richly decorated
zebra? Before attempting to answer this important and,
it must be confessed, difficult question, let us see to what
extent some of the horses of to-day are striped, and the
nature of the pattern. Fuirst-hand evidence in matters of
this kind is most valuable. I shall, therefore, in dealing
with the striping of the horse, refer almost exclusively to
stripes present on the horses I have specially examined
during the last three years.

Head Stripes.—In a sand-coloured (yellow dun) Nor-
wegian pony, with black mane and tail, which has been
in my possession for over a year, there are stripes on the
face, neck, body, and legs.* On the forehead there are two
all but complete frontal arches and portions of five others
(Fig. 36). Being of a reddish-brown colour these stripes are
easily seen when the forelock is thrown back. The upper-
most (orbital) arch ends in the frontal tuft, but instead of
forming an acutely pointed arch, as in Matopo, it forms a
somewhat rounded arch, as in the Amsterdam quagga and
in one of my zebra hybrids. ‘he fragments of the other
arches are most distinct in the middle of the forehead.
In having seven more or less complete frontal arches this

* T may mention that this is a typical Norwegian pony, the dam of which

I have no hesitation in saying never had the opportunity of even seeing a
zebra.

TELEGONY AND REVERSION. 1038

pony differs from my Burchell zebra, in which there are
only three distinct arches in the corresponding position.
When the incomplete arches are “restored” a pattern is
formed which is almost intermediate between that of the
Amsterdam quagga and the Somali zebra. From within
the lowest arch several obscure lines, such as occur in

Fic. 36.

Norwegian Pony.
zebra-ass hybrids, can be traced along the face. The
stripes doubtless originally ended in or near a mealy-coloured
muzzle, such as we find to-day in typical Exmoor ponies
and in some Somali zebras. I have seen only two ponies
with stripes on the face, and I imagine facial stripes are

104 TELEGONY AND REVERSION.

extremely rare. Darwin as a youth seems to have been
devoted to horses. When at Cambridge he had a passion
for shooting and hunting, and when that failed riding
across country. This may partly account for his great
interest in horses in after years, tor his systematically
collecting information about horses from all parts of the
world, that he might, if possible, come to some conclusion
as to the original colour and markings of their less remote
ancestors. Apparently Darwin only once noticed stripes
on the face. This was ina cob-like fallow-dun having a
conspicuous spinal stripe and its front legs well barred.
Darwin, however, learned from Colonel Poole that Kattia-
war horses had often “stripes on the cheeks and sides of
the nose.’* I have only seen faint indications of stripes
on the sides of the face, but from what I have seen I have
no hesitation in saying that were a sketch made showing
all the stripes of which fragments have been observed on
the face of the horse during the present generation, the
sketch would closely resemble the head of one of my
hybrids and less closely the Amsterdam quagga. As
stripes on the forehead in the form of acutely pointed or
rounded arches are, as far as Iam aware, only found in
the horse family, and as stripes are evidently being
gradually eliminated in horses, most will agree with me
that the facial stripes in the Norwegian pony are not new
creations, but vestiges of ancestral markings.t As to the
ears, I may mention I have seen two light dun-coloured
ponies—one from Shetland and one from Norway—with
the tips for quite half an inch almost white. In both cases
a dark broad band extended across beneath the hight tip.
In the Norwegian with the striped face there are only a

* © Auimals and Plants,’ vol. i, p. 61.

+ Were they new creations they would, if the usually accepted view as
to the origin of stripes is correct, in all probability consist of rows of spots
in process of blending, instead of narrow, more or less distinct lines.
Further, the “blaze,” so common in some breeds—whether in the form of
a lozenge or of along white patch extending to the muzzle,—is easiest

accounted for by supposing the face of the ancestral horse resembled that
of the quagga or one of the zebras.

TELEGONY AND REVERSION. 105

few light hairs at the tip of the ears, but immediately
below there is a broad black band, and an indistinct band
near the base. Had the tip been lighter in colour the ear
of this pony would have not a little resembled in its
decoration that of my Burchell zebra.

Neck Stripes.—The Norwegian pony has only a short
shoulder stripe, but in an old bay Highland cob in my
possession a year ago the shoulder stripe was nearly a foot
in length. Sometimes the shoulder stripe bifurcates some
distance above the level of the shoulder-joint, and thus
suggests not so much the zebra as the quagga and zebra
hybrids. In the Norwegian pony there are a number of
ill-defined stripes in front of the shoulder stripe, and in
another light dun-coloured pony there are ten cervical
stripes. As these ten stripes only extend about halfway
along the neck, and as stripes are sometimes present
immediately behind the ears, there may have been quite
twenty stripes in the ancestors. As a rule the neck stripes
are short and indistinct, but in the Highland cob one
extended quite two thirds across the neck; and in some
cases I have seen three or four cervical stripes nearly as
well defined as in the zebras. In one case I observed
several stripes extending into the mane.

Body Stripes—In the Norwegian with the partially
tattooed forehead there are only three short stripes on the
body behind the shoulder stripe, but there were six in the
Highland cob. Mr. Darwin, in discussing striping in
horses, says, “Stripes on the body, not to mention those
on the legs, are extremely rare—I speak after having long
attended to the subject —with horses of all kindsin Europe,
and are unknown in the case of Arabians.”* I have, how-
ever, before me a photograph of a mouse-dun Norwegian
pony showing vestiges of stripes nearly as far back as the
loins—as far back as in the Gore Ouseley filly (Fig. 15).
But it is not only important to prove that there were stripes
ou the body, but also to determine if possible their
number and direction, and to ascertain whether they most —

* © Animals and Plants,’ vol. i, p. 435.

106 TELEGONY AND KEVERSION.

agreed in their disposition with those of the Burchell,
the mountain, or the Somali zebra. In the yellow-dun
Norwegian there is an extremely well developed dorsal
band, as distinct and as broad as it crosses the croup as in
my Burchell zebra. Darwin says, “I have never heard of
either shoulder or leg stripes without the spinal stripe.”’*
The spinal stripe or dorsal band, in fact, occurs more or less
constantly in all the species and varieties of the horse
family. This band and the leg stripes are so common and
persistent that it looks as if they had either been estab-
lished long before the other stripes or retained long after
the stripes on the face, neck, and body had all but dis-
appeared.

When one looks from a height on the dorsal band of
the Norwegian pony, the edges are seen to give off short
processes—rudiments of developing stripes or vestiges of
dwindling ones, such as are seen in some of the quaggas
and in zebra-ass hybrids. Once, and once only, have I
seen as many as five distinct stripes extending from the
dorsal band across the back. Evidently vertical stripes
on the body, as Darwin observed, are extremely rare—
almost as rare as on the face.

But although well-defined stripes are seldom seen on the
trunk, obscure delicate lines may often be detected running
down the sides of the body and across the flanks in horses
of all breeds and colours. ‘These lines I first noticed last
May in a dark yellow-dun Canadian maret—they were
gradually revealed as the winter coat was shed. These
lines, which vary in width from an eighth toa quarter of
an inch, though in most cases difficult to see, are some-
times (when lighter in colour than the intervening spaces)
quite distinct. Usually they are most evident when the
“staring” slightly. At times, as Mr. Alexander,
R.S.A.,{ said, they remind one of the lines on a roll of

coat is

* © Animals and Plants,’ vol. i, p. 63.

+ This and another mare Mr. Stewart, cab proprietor, Dean Bridge,
Edinburgh, was good enough to lend me for some weeks last spring.

+ I am not aware of any reference to these lines by recent writers

TELEGONY AND REVERSION. 107

bacon—the lines produced by the string with which it is
for a time encircled. In the yellow-dun Canadian mare
there are seventeen lines between the elbow and the stifle,
separated by spaces about two inches in width. The four
most posterior arch upwards in front of the stifle, and
then curve backwards across the flank feather. ‘The lines
which cross the lower part of the feather are quite evident
in the majority of horses; they are particularly distinct in
two of my chestnut mares, and in an almost white Arab
mare. All but continuous with these ‘‘feather”’ lines I have
seen ill-defined markings extending right across the hind
quarters of two bay horses of the Shire breed. In front
of the recurved lines there are in the Canadian mare
thirteen others, which occupy a nearly vertical position.
Some of them incline forwards as they pass behind the
elbow, to end in what might be described as an indistinct
ventral band ;* while others bend slightly backwards. In
Mulatto relatively broad vertical lines are especially dis-
tinct. Beginning some distance behind the shoulder-blade,
within seven or eight inches of the spinal ridge, they run
down the sides of the body towards the ventral surface.
At a distance of twelve yards seven lines can be easily
recognised, the second forking about the level of the
shoulder-joint, after the manner of the body stripes in
some zebras and zebra hybrids. In some cases I have
seen lines running obliquely upwards above the level of
the flank feather. These delicate and faint flank markings
(which are distinct enough in a yearling chestnut fillyt to
admit of their being photographed) are especially interest-

Mr. Alexander alone, of all those wise about horses I have consulted,
had seen them; he has even tried to represent them in some of his
pictures.

* One of the recognised differences between recent horses and their
allies, the zebras, is the absence in the horse of a ventral band; but in
the Canadian mare an indistinct band, about a foot in length, extends
along the breast-bone.

t This filly belongs to the Walltower Stud Farm. To the owners
(Messrs. Cairns) I am indebted for many favours during the last two years.

108 TELEGONY AND REVERSION.

ing, because they closely correspond to narrow stripes in a
similar position in my zebra hybrids.

Have these various lines any significance? Are they
due to rows of hair lying at an unusual angle, or to
furrows in the skin, or are they the last remnants of
ancestral stripes, or of the spaces between stripes ?* Some-
what similar but more prominent lines occur in Indian
cattle, the ancestors of which were probably striped, and
also in mules, and in some of my zebra hybrids. Taking
into consideration that these lines in their arrangement
agree more or less accurately with the stripes in the
mountain zebra, and with the fragments of stripes in
Norwegian and other ponies, I am inclined to the view
that though not necessarily vestiges of stripes they indicate
where the ancestral stripes occurred. AJ] we know as to
the origin of stripes is against the supposition that the
lines are the rudiments or forerunners of stripes by-and-
by to be evolved.

Let us now inquire if stripes occur across the croup
(sacral region) and rump—the region lying between the
croup and the root of the tail. Darwin describes stripes
in this region in a foal of his own breeding. After men-
tioning that almost the whole body was marked with very
narrow obscure stripes, he says the “stripes were distinct
on the hind quarters where they diverged from the spine
and pointed a little forwards.’’ Darwin does not seem to
have observed stripes across the croup in a full-grown
horse. Such stripes are, however, said to occur even in
horses having a large proportion of Eastern blood. I have
before me a drawing of a well-bred Austrian mare which,
in addition to shoulder stripes and stripes on the face,
neck, and legs, and across the root of the tail, had three
stripes across the hind quarters. One of these runs

* IT may mention that the stripes have no relation to the ribs or to the
course of nerves or blood-vessels in recent zebras, but they may have
run parallel to nerves or blood-vessels in the ancestors of the zebras.
Some of them, however, correspond closely to wrinkles which occasionally
appear on the skin; but this does not hold for the neck stripes.

VELEGONY AND REVERSION. 109

obliquely backwards and outwards across the croup, while
the two others extend across the rump. In their direction
these markings probably differed from the stripes on the
“hind quarters” of Darwin’s colt, from the rump stripes in
the common zebra, and, as will appear later, from markings
across the croup in Mulatto’s second foal. As stripes in
the horse have long counted for httle or nothing in the
struggle for existence, these oblique stripes may not bear
any relation to ancestral markings. Although I have
never seen transverse markings across the croup and
rump of horses—markings such as characterise the
common zebra—it does not follow they never exist. It
is quite conceivable that in some breeds of horses they are
comparatively common. It may be here mentioned that
indistinct markings were sometimes present on the hind
quarters of the quagga ; that irregularly arranged spots are
very common over the hind quarters of zebra-ass hybrids,
and that, as already mentioned, there were at birth spots
over the croup and rump of Romulus. These facts point
to the croup and rump stripes having been acquired com-
paratively late in the zebras, and to their having begun to
vanish almost before they were firmly established—before
they were sufficiently burned in to persist when neglected
by natural selection. On the other hand I have frequently
seen a cloudy patch over the croup and rump of bay horses
which seems to indicate that in the horse stripes persisted
long over the hind quarters.

Leg Stripes.—I have only now to refer to the striping of
the legs. So common are stripes on the legs of horses, that
whatever is thought as to the presence of stripes on the
face or body, no one seems to doubt that the legs of the
ancestors of the horse were provided with numerous trans-
verse markings. Leg stripes, more especially in the
vicinity of the knee (wrist) and hock (ankle), seem to be
nearly as old as the dorsal band. In some yellow and
mouse duns I have seen stripes on the fore limb from the
fetlock up to within a short distance of the elbow, and
on the hind limb a considerable distance above the hock.

110 TELEGONY AND REVERSION.

As in the zebras, the stripes are sometimes distinct, at
other times they have more or less run together. In
some zebras the leg below the knee is almost black ; perhaps
the much admired “ black points” of the favourite bay
have resulted from the fusion of ancestral stripes on the
lower part of the legs.

From a consideration of all the stripes I have seen on
horses, I have come to the conclusion that the ancestral
horse was in its markings nearly intermediate between the
common and the Somali zebras. In Romulus we may have
a fairly accurate restoration of the stripes in the ancestors
of the Burchell zebras and, though less likely, also of some
of the markings in the ancestral horse.

Having indicated to what extent recent horses may be
striped, the mane and tail may next be considered. The
attempt to arrive at any conclusion as to the mane and
tail of the ancestral horse may seem quite hopeless.
Endeavouring to settle whether the mane was long and
lank, or short and upright, and whether the tail could only
boast of long hairs at the tip, in say the horse of the
Pliocene epoch, may seem to some attempting the im-
possible. We sometimes hear of paleeozoologists recon-
structing an entire skeleton from a single bone—it may be
from a single tooth. I think we have the equivalent of at
least a fossil tooth in the markings on the face of the
Norwegian pony. These markings, distinct enough now
(October), were strikingly evident in May, after the winter
coat was shed. Nevertheless they were unobserved for
months, for the simple reason that they were hidden under
a massive forelock. I may again say that I look upon the
incomplete stripes on this pony’s forehead as relics of a
time when the horse had a striped face, not as rudiments
of stripes in process of development. Stripes are almost
invariably preceded by spots not very regular in their
arrangement—spots that if joined in one way give longi-
tudinal stripes, if in another transverse. The evolution of
stripes such as we find in zebras must have occupied count-
less ages, and their maintenance in a complete form must

TELEGONY AND REVERSION. 111

have involved the suppression of not a few interesting varia-
tions. It is almost inconceivable that nature would decorate
the brow of a horse after the pattern of a zebra if the work
when completed would never be seen. Hence we may take
one of two things for granted; (1) either that the process
of tattooing is proceeding now, or (2) that the brow mark-
ings are vestiges of stripes which existed in, and were of
use to, the ancestors, before a great frontal bunch of hair or
forelock made its appearance. That the last supposition
is most in keeping with what we know of nature’s methods
will be at onceadmitted. But if the forelock was originally
so short that the frontal stripes were visible, the mane
must also have been short ; for the forelock is not a special
growth, it is nothing more nor less than the most anterior
part of the mane, that part of the mane which lies between
and infront of the ears. In other words, the period in the
ancestral history of the horse characterised by a complete
series of facial stripes was, it may be inferred (if the stripes
were of any use), also characterised by a mane consisting
of short nearly upright hairs which were annually shed.

In support of the view that the primeval horse had a
short upright mane, it may be mentioned that in colts
the mane is as a rule upright for several months, and that
it sometimes eventually falls to the right side, sometimes
to the left, sometimes partly to one side in front and to the
other side further back. Further, when in Norwegian dun
ponies the long dark central hairs are cut, the finer lght-
coloured hairs at each side naturally assume an erect
attitude. Of still more importance is the fact that the wild
Tarpan, to which some of our recent horses are doubtless
related, had an erect or nearly erect mane, the central
hairs of which were presumably annually shed.* The
retention of the hair of the mane until it reached a con-
siderable length may have been found useful, especially
when lying down, to horses living in cold, damp, northern
areas, where stripes were of little or no value.

* The mane is said to be still sometimes upright in the domestic horse,
and it is represented as erect in paleolithic etchings.

112 TELEGONY AND REVERSION.

In all probability the hair of the mane lengthened and ~
became more persistent as the hair of the body increased
in length and thickness. That the coat became thicker and
longer as the horse extended its range to mingle with the
reindeer and the other tundra fauna may be taken for
eranted. While the long hairs of the mane and tail were
probably first acquired by natural selection, they may have
been retained and lengthened by artificial selection. The
Arab, probably evolved in a cold area, has retained the
long mane and tail; but the hairs, like those of the body
generally, are apt to be fine and silky. Occasionally,
according to Azara, horses were born in Paraguay with
hair like that on the head of a negro. In such horses the
mane and tail were short—they were, in fact, curiously
correlated to the hair on the body.* This further supports
the view that the long mane was acquired after the horse
left its ancestral home—perhaps long after it migrated
from the New into the Old World.

There is in the horse family for some reason or other
always an intimate relation between the condition of the
mane and that of the tail. In the recent horse the mane
consists of long persistent hairs (sometimes the mane has
been over six feet in length), and the tail also from within
two or three inches of the base to the apex of the dock
consists of persistent hairs, those growing from the tip
being sometimes long enough to reach the ground. In the
zebra, as already stated, the mane, as arule, consists of short,
upright, deciduous hairs, while the tail, though having long
persistent hairs at its tip, has deciduous (never very long)
hairs elsewhere. In zebra-horse hybrids the hair in the
mane, though sometimes double the length of that in the
zebra, seems to be shed annually ; + and though there are
longish hairs up to the base of the tail, only the long hairs
springing from and near the tip persist. That the tail in

* © Animals and Plants,’ vol. i, p. 56.

+ Ihave seen a zebra in which the mane, as in zebra hybrids and in the
ass of Somaliland, was long enough to fall slightly backwards and to one
side ; a further development might result in a horse-like mane.

TELEGONY AND REVERSION. 1138

the ancestral horse resembled that of the zebra of to-day
may also be gathered from astudy of its development. In
the embryo the tail is at the outset not only quite hairless,
but much longer than the hind limbs. By-and-by the limbs
grow so rapidly that the tail hardly reaches as far as the
hocks. At about the eighth month of foetal life the tail
(with the exception of its tip) is covered with quite short
hairs; the tip has already longish hairs. In fact, the
history of the development of the tail, asfar as made out,
seems to indicate that in the remote ancestors of the horse
there were long hairs at the apex only, as in the Somali
zebra; that in less remote ancestors less long but deci-
duous hairs extended up to within a short distance (six or
seven inches) of the root, as in the Burchell zebras; and
that eventually, as the hair began to persist in the mane,
persistent hairs appeared up to, or almost up to, the base
of the tail, as in our recent horses.

What answer shall we now give to the question: Have
our horses descended from striped ancestors? Taking
into consideration the facts I have mentioned, and espe-
cially (1) that there are more or less striped horses in all
parts of the Old World; * (2) that in Mexico and various
other parts of the New World the descendants of horses
introduced by the Spaniards are frequently dun-coloured
and provided with dorsal and leg stripes; t (3) that foals
are often partially striped, one bred by Darwin being
marked all over with obscure narrow stripes; and (4)
that mules (hybrids between the jackass and mare) have
frequently leg stripes as well as spinal and shoulder
stripes—taking these and other facts into considera-
tion, the conclusion may be hazarded that the ancestors
of all our horses were striped, and that the stripes
were arranged more after the plan in the common than
in that of the Burchell zebra. If we agree with Darwin
“that not even a stripe of colour appears from what is

* See ‘ Animals and Plants,’ vol. i, p. 61.
+ Nature, March 11th, 1897.

114 TELEGONY AND REVERSION.

commonly called chance,”’* I fail to see what other

conclusion could be arrived at.

Reversion in the EHquidex.

Having given reasons for the belief that the ancestors
of the horse were striped—striped more or less after the
pattern of the mountain zebra,—the important question
may now be asked: Do horses without so much as a dorsal
band sometimes bring forth offspring with a considerable
number of stripes? and the still more important question :
Are the stripes in such offspring due to reversion? It is
widely believed that stripes are not very uncommon at
birth even in Arabian foals. I may add some recent
evidence in support of this belief. Two yearsago I bred a
foal from a black Shetland pony, the siret being also
black and of the same strain as the dam. The foal, which
was of a reddish dun colour, presented at birth the fol-
lowing stripes :—(1) a dark dorsal band which extended a
short distance into the tail; this band widened as it
reached the croup, and again, as in many zebras, con-
tracted as it approached the root of the tail;{ (2) a
shoulder stripe over six inches in length ; (3) one distinct
and five indistinct stripes on each side of the neck imme-
diately in front of the shoulder stripe, and three on the
body behind the shoulder stripe; and (4) a number of
very obscure stripes on the legs. In this foal the mane
was black and at first nearly erect, while the tail was of a
dark grey colour. When six weeks old the foal began to
shed its coat, and when two months old the markings had
completely disappeared from the legs and the sides of the
body, and they were less distinct on the neck. Whena
year old this colt was of a dark bay colour, but only re-

* Origin of Species,’ p. 129.

+ The sire was Wallace, a champion Shetland pony.

{ When the foal was two months old, this band consisted mainly of
erect reddish hairs (such as I have seen in zebra and zebra hybrid foals),

from which one is tempted to infer that in the remote ancestors of the
Equide the mane extended right along the whole length of the back.

TELEGONY AND REVERSION. 115

tained the dorsal band and two stripes across each shoulder.
It may be well to point out that both the dam and the sire
may have been striped at birth, and that had they been
bay instead of black, some of the stripes might have been
visible throughout life.*

Mr. Wilfrid Scawen Blunt has been good enough to
send me some particulars as to his 1897 crop of Arab foals.
Mr. Blunt has this year ten foals from pure Arab mares,
all the foals having as their sire Mesaoud, a bright
chestnut Arab with four white legs and a blaze. Of seven
bay mares, five had bay foals while two had chestnut foals.
Of the five bay foals two had a dorsal band. One of the
mares which, like the sire, is a chestnut had a chestnut
foal with a dorsal band. Of the two remaining mares one
is grey, the other white; the grey mare had a bay foal, the
white a chestnut, showing distinct zebra markings inside
the forearms, less distinct markings above the hocks, and
a hardly perceptible line down the spine. Mr. Blunt in-
forms me that the dam of this striped colt is absolutely
pure white (and, like the sire, of the most perfect Arab
type); that he has noticed that stripes occur most fre-
quently in foals from white parents, but that the stripes do
not outlast the second year, or at longest the third. The
desert Arabs seem to dislike dun-coloured horses, and, pro-
bably owing to the duns being weeded out, stripes are
comparatively rare in desert-bred high-caste Arabians.
Nevertheless four (7.e. 40 per cent.) of Mr. Blunt’s 1897
Arab foals had a dorsal band, and one in addition stripes
on both the fore and hind legs. It is especially interesting
to note that all the ten foals were either bay or chestnut.
The foals of grey horses are never born grey; with few
exceptions, foals at birth belorg to the red or mouse dun
series of colours—are bay, chestnut, or brown. Jf both
parents are of the same colour and strain and inbred, the
foals may closely resemble the parents even if they are
black or cream-coloured or piebald.

* Is it possible that we owe our black horses to the blending of dark
ancestral stripes P

116 TELEGONY AND REVERSION.

We can only guess as to the colour of the remote
ancestor of the horse, but nearly all who have made a
special study of the subject have come to the conclusion
that the less remote ancestors were dun-coloured. But it
is hardly sufficient to say the ancestors were dun-coloured,
for in Norway four shades of dun are recognised, which
include nearly every colour from white to black. There
are (1) white duns (white and light creams) with white
mane and tail; (2) yellow duns with black mane and tail,
including creams and light bays; (3) elk duns, frequently
approaching in hue bays, chestnuts, and browns ; and (4)
mouse duns, some of which are nearly black. After a full
consideration of the subject, I am inclined to believe the
body colour of the striped ancestral horse of the temperate
regions was mainly of a yellowish brown colour. As the
descendants extended their range the ground colour would
change, a sand colour probably prevailing in desert areas,
a reddish dun in the vicinity of forests, a mouse dun in
the far north, a light tint near the tropics, and in the
uplands a grey or ash tint.

From various experiments made it seems to me that
black, white, grey, and cream-coloured horses, even if
striped, would have little chance of surviving long enough
in a wild state in the Northern Hemisphere to form black
and other conspicuously coloured breeds, and that the most
serviceable colour for northern horses, i.e. the most
protective colour, would be an indescribable shade of dun
approaching a sand colour on the one hand, and a dull
lustreless light bay on the other. The least conspicuous
pony in my possession is a typical Exmoor with the
characteristic mealy-coloured muzzle, black points, and
the body generally of a yellowish brown or dirty bay shade,
the belly and upper parts of the inside of the legs being
. of a uniform dirty white. -

Black, flea-bitten, cream, and skewbald ponies are in
most circumstances extremely conspicuous, while the
mouse and dark yellow duns, the bay and brown ponies,
and the ash-grey or khaki-coloured asses are in some lights

TELEGONY AND REVERSION, 117

often hard to see. Froma yellowish brown tint the various
shades of yellow, red, and mouse duns might be easily
derived; and from a combination of these shades the
formation of bays, chestnuts, and browns would be only
a matter of time or of artificial selection.

In the foals of all shades of Arab, English, Norwegian,
and Iceland horses, being with few exceptions at birth of
a bay or chestnut tint, and frequently provided with a
dorsal band and with leg stripes which ordinarily dis-
appear, we have, it seems to me, evidence of reversion.
For a remarkable instance of the transitory striping of a
foal we are indebted to Darwin. In a chapter bearing on
the colour and stripes of the horse he says: “The most
interesting case which I have met with occurred in a colt
of my own breeding. A bay mare (descended from a dark
brown Flemish mare by a light grey Turcoman horse) was
put to Hercules, a thoroughbred dark bay, whose sire
(Kingston) and dam were both bays. The colt ultimately
turned out brown, but when only a fortnight old it was a
dirty bay, shaded with mouse grey, and in parts with a
yellowish tint; it had only a trace of the spinal stripe,
with a few obscure transverse bars on the legs, but almost
the whole body was marked with very narrow dark stripes,
in most parts so obscure as to be visible only in certain
lights, like the stripes which may be seen on black kittens.
These stripes were distinct on the hind quarters, where
they diverged from the spine and pointed a little forwards ;
many of them as they diverged became a little branched,
exactly in the same manner as in some zebrine species.
The stripes were plainest on the forehead between the ears,
where they formed a set of pointed arches one under the
other, decreasing in size downwards towards the muzzle ;
exactly similar marks may be seen on the forehead of the
quagga and Burchell’s zebra.* When this foal was two
or three months old all the stripes entirely disappeared.” T

* A figure showing the extent or arrangement of the stripes on this

colt would have been invaluable.
+ ‘Animals and Plants under Domestication,’ vol. i, 2nd edit., p. 60.

118 TELEGONY AND REVERSION.

As no mention is made as to the existence of stripes in the
immediate ancestors of this striped foal, it may be taken
for granted that they were whole-coloured. But one at
least of the parents may have been striped at birth. On
reading the description of Darwin’s colt with the all but
invisible stripes it naturally occurs to one that many foals
may be striped at birth, but owing to the lines being so
subtle they escape the notice of the ordinary observer ; and
further, that foals not showing stripes at birth may have
passed through a striped stage before birth.

A year ago Mr. Selous was good enough to tell me of
some of his experiences with zebras in South Africa. I
was particularly anxious to learn about the coloration of
unborn zebras. The origin of stripes has long interested and
puzzled naturahsts. It has been suggested that transverse
stripes are preceded by longitudinal bands, the longitudinal
bands undergoing a kind of segmentation, the segments
being afterwards joined together to form transverse stripes.
Fortunately Mr. Selous had seen an unborn zebra, which
though distinctly striped looked as if it was quite destitute
of hair. But as the zebra’s skin is of a nearly uniform
dark colour throughout, there can be no doubt that with the
help of a lens hair rudiments at least would have been
detected in this foetus. From the information Mr. Selous
was able to give, and from an account of a foetal zebra
given by Sparman, I am satisfied that the transverse
stripes of zebras are not preceded by longitudinal bands.
In young zebras the stripes have often a wavy, almost a
zigzag appearance. Hence the transverse stripes, though
not derived from longitudinal bands, may in some cases be
represented for a time by spots, which by being somewhat
out of line give rise when welded together to more or less
wavy stripes. Are the horse foals, which are whole-
coloured at birth, marked like a zebra before birth ? or, Is
the striped phase in the ancestral history frequently entirely
skipped by an abbreviation in the development process?
As I have in my possession a series of foetal horses ranging
from three weeks to over ten months, I am able to state

TELEGONY AND REVERSION. 119

definitely that all horse-foals do not pass through a striped
stage. On the other hand, though a dorsal band and leg
stripes are present in one of the parents, the offspring may
be quite devoid of stripes. The most remarkable instance
I have come across of stripes being few and obscure in the
offspring, though plentiful in one of the parents, is a zebra
hybrid (Fig. 37) bred by Lady Meux.* The dam in this
case was a Burchell’s zebra mare (the skin, Fig. 38, of

Fic. 37.

Zebra @ horse & Hybrid. (Bred by Lady Meux.)

which has been preserved), the sire a small wall-eyed light
bay pony (Fig. 89). The zebra mare had previously borne
two foals striped after the manner of my zebra-mare hybrids.
The sire of one of these foals, I understand, was a bay pony,
of the other a brown pony. Why the third foal was obscurely

* To Lady Meux, of Theobald’s Park, Hertfordshire, I am indebted for
the permission to have photographs taken of her three extremely interesting
horse @, zebra 2 hybrids.

120 TELEGONY AND REVERSION,

striped is an interesting problem, which need not be here
considered. The point of interest is that a profusely striped
dam belonging to an ancient wild species should have pro-
duced an obscurely striped foal to a cross-bred pony, the
ancestors of which have long been under domestication.

It thus appears that parents devoid of stripes may have
more or less striped offspring; that all foals do not pass
through « striped stage during development; that foals
may lose the majority of their stripes soon after birth, and
that though one of the parents is striped all over, the

Skin of the Dam of Lady Meux’ three Hybrids.

offspring may ouly possess faint indications of zebra-like
markings.

Having seen that foals have often stripes at birth which
afterwards disappear, the question of go vital importance
in;connection with telegony may now be asked: Are the
stripes often found on foals due to reversion or atavism ?
A direct answer to this question is of course impossible

a . . . Py 2
but an answer sufficiently convincing may be arrived at by
the deductive method.

It seems to be admitted that all the breeds of pigeons

YELEGONY AND REVERSION. 121

have descended from the blue rock pigeon (Columba livia),
and it has long been known that when distinct varieties of
pigeons are crossed, the young sometimes very closely
resemble blue rocks. Mr. Darwin refers to a pigeon
descended from a red spot and a white fantail on the one
side, and two black barbs on the other. This pigeon was
hardly distinguishable in its coloration from a wild rock
pigeon.* Darwin accounted for the occasional resemblance
of cross-bred pigeons to the rock pigeon, by saying they had

Fic. 39.

Sire of Hybrid shown in Fig. 37.

undergone reversion. ‘To quote from Weismann: “ Darwin
was the first to point out that in cross-breeding, either of
species or of mere varieties, characters not infrequently
appear in the descendants which were not present in the
parents; in some of which cases, indeed, it can be
proved, and in others shown to be very probable, that they

* © Animals and Plants,’ vol. ii, p. 14.

122 'ELEGONY AND REVERSION.

have been derived from remote ancestors.” * Reversion
has, many think, been proved to occur in pigeons, and it is
said to be very probable in the horse family. In Chile,
horses living under conditions not unlike those enjoyed by
their ancestors in Andalusia, are said to have remained
unaltered ; whereas in the eastern parts of South America
the horses some years ago were chiefly dun-coloured with
large coarse heads. Darwin thought this difference might
also be due to reversion.t Mr. T. D. A. Cockerell recently
pointed out that “in New Mexico one frequently sees small,
usually pale yellowish-brown horses, with extremely well-
marked leg stripes.” He believes the small horses ‘are
descendants of the horses which ran wild in former years
over New Mexico,” and that there can be little doubt “ that
they represent an atavistic variety.” {

But hybrids between members of the horse family afford
still stronger evidence of reversion. Lord Morton’s quagga
hybrid, though but faintly striped on the body, had distinct
transverse bars ou the legs, ¢. e. stripes which were neither
present in the dam nor in the quagga sire; and many mules
have often leg stripes, and occasionally shoulder stripes in
addition to a dorsal band. Some months ago I saw in
the South of France a light-coloured mule with the legs
striped as distinctly as in the ass of Somaliland. Fre-
quently, though there are numerous stripes on the mule,
neither the sire nor dam has either leg or face stripes.
I have already described at some length the plan of the
stripes in my yearling hybrid. From this description it
appears that Romulus differs in a most pronounced manner
in the number and arrangement of his stripes, not only
from his sire but from all the varieties of the Burchell
group of zebras. But if one may judge from the markings
on the Norwegian with the striped face, Romulus also

* ©The Germ-plasm,’ p. 316.

+ ‘Animals and Plants,’ vol.i, p. 54; vol. ii, p. 6.

£ Nature, March 11th, 1897, p. 489. Iam indebted to Mr. Cockerell for
a photograph showing the leg stripes in one of these New Mexican ponies.

TELEGONY AND REVERSION. 128

differs in his markings from the less remote ancestors of
his dam.

To recapitulate: Romulus, in having numerous narrow
arches across the forehead, differs greatly from his sire,
and in a less degree from the Norwegian pony; in having
twenty-four cervical stripes he differs from his sire, but
closely agrees with the Transvaal zebra filly when the
shadow stripes are included; in having over forty stripes
between the shoulder stripe and the root of the tail he
is surprisingly unlike his sire, in which there are only
five distinct transverse body stripes; and in having at
birth well-defined spots over the croup and rump, he
differed not only from his sire but from all the other
zebras; and if in Mr. Darwin’s striped colt we had a
restoration of a lost chapter in the history of the horse,
Romulus also differed in this respect from the less remote
ancestors of his dam. As already pointed out, Romulus
in the brow markings and in the numerous stripes running
at right angles to the dorsal band, more or less accurately
agrees with the Somali zebra, with which he also nearly
agrees in the relative length of the head, the markings
within the two divisions of the shoulder stripe, and over
the rump and hind quarters. Further, at birth his muzzle
resembled in colour that of the Somalland zebra. These
resemblances to the Somaliland zebra become doubly
interesting when it is remembered that there are excellent
reasons for believing this zebra to be more primitive than
all the other living zebras. They, in fact, all but prove
that in the striping of Romulus we have a remarkable
instance of reversion. Additional evidence of reversion
we seem to have in the intermediate spaces in the hybrids,
being at first of a yellowish-brown colour, and the mane
being nearly upright, and in the tail having only persistent
hairs at the tip. But even stronger evidence in this
direction is afforded by the spots which at birth were
scattered over the hind quarters. I am satisfied these
spots have no relation whatever to the dappling so often
seen in recent horses. Dappling, I believe, has been

124, TELEGONY AND REVERSION.

acquired since the ancestral stripes were all but lost.
When dappling co-exists with more or less distinct stripes
it is at once evident from the relation of the dappling to the
stripes that the one has not been derived from the other.
The pigment which formerly produced stripes (now no
longer counting in the struggle for existence, and hence
neglected) has in recent times been as it were left uncon-
trolled, with the result that it frequently gives rise to ever-
varying and quite meaningless dappling, or to large equally
meaningless blotches.

We look upon the spots on the young lon as ancestral
relics, as indicating that lions (which are now in their
colouring best adapted for a lfe in the desert or the open
veldt) were at one time adapted for a jungle or forest life.
Tn the same way, from the spots which frequently appear
in young pigs and afterwards unite to form bands, we
areve that the remote ancestors of the pigs were spotted,
while the less remote ancestors were characterised by
longitudinal bands. There are various cogent reasons for
believing that stripes were in many cases preceded by
spots, and we know that animals frequently during develop-
ment and growth repeat more or less accurately certain
phases of their ancestral history. The fact that the spots
over the hind quarters of Romulus have, since his birth,
to a considerable extent blended to form stripes, which
almost agree line for line and curve for curve with the
croup and rump stripes in the Somali zebra, seems to me
to be only capable of one explanation. In the spots we
have restored by what we term reversion or atavism a lost
stage in the evolution of the stripes over the hind quarters
in the Equide; and by the gradual blending of the
majority of these spots during the first year of the hybrid’s
existence, we have had a practical demonstration of how
some of the stripes on the Equide were originally formed.

If the difference between the markings in Romulus and
his sire are not due to reversion—to the restoration in a
modified form of one of the phases through which, it may
be, both horses and zebras passed during their evolution,

TELEGONY AND REVERSION. 125

how are they to be accounted for? The only other feas-
ible explanation that occurs to me is, that in the numerous
stripes across the sides, and in the spots over the hind
quarters of Romulus, we have an instance of an abrupt
form of variation. On this assumption, the resemblance
of Romulus in his markings to a Somaliland zebra must
be considered a mere coincidence.

The evolution of stripes in the Equidee doubtless occupied
many centuries. Stripes imply at the outset a concentra-
tion of pigment in certain definite areas, and later the
disposition of the pigment to form hardly appreciable ill-
defined bands, or it may be to first form irregularly arranged
spots, which afterwards unite to form wavy bands, the
edges of which are later smoothed. But stripes in the
zebras also imply a lightening of the intermediate spaces
and other intricate and complex changes. By examining
the hair of Romulus one seems to get a hint of how the
striping has been brought about. The hairs making up
many of the dark bands are at their inner ends of the same
or almost the same colour as the inner ends of the hairs
in the light intermediate spaces. At present (October) the
hairs in the region of the shoulder are quite two inches in
length. If some hairs are taken from the shoulder stripe
and others from one of the light-coloured spaces near the ~
shoulder-stripe, the inner ends of both samples are seen to
be of a yellowish-grey or ash colour. But while the inner
ends agree, the outer two thirds or so distinctly differ.
The hairs from the dark stripes for quite two thirds of
their length are dark brown or almost black, while the
hairs from the light space are for quite two thirds of their
length of a pale ash colour, while the remaining third—
the outer or distal part—is of a light brown colour.* It is
doubtless possible that the result of crossing extreme forms
may be the formation of new and unheard of varieties—
may, in fact, lead to progressive changes ; but for reasons
to be given later I consider that this but seldom occurs,
that in fact the intercrossing of extreme forms must almost

* The difference in the colour of the hairs is more pronounced in summer.

126 TELEGONY AND REVERSION.

of necessity result in what might be termed retrogressive
changes—result in something more than mere arrest in
development. The crossing of two distinct varieties or of
two well-marked species might very well be expected to
result in an intermediate form; but owing to the antago-
nism between the units of germ-plasm derived from two
dissimilar individuals, it is undoubtedly to many all but
inconceivable that crossbred progeny should possess in an
exaggerated form the characters of either of the immediate
ancestors. We might a priort as well expect a mixture
of red and blue sand to be intensely red or intensely blue
rather than purple.

Nevertheless, the numerous stripes across the face and
body of Romulus and the spots over the hind quarters
may after all be due to discontinuous variation. Hence
although Darwin was wont to ascribe to reversion the
appearance of transitory stripes on foals, and the more
permanent stripes on mules, it will be well to consider
whether the zebra hybrids do not in their coloration
afford a striking instance of discontinuous variation.
Bateson in his suggestive work on variation says, “‘ Around
the term reversion a singular set of false ideas have gathered
and that “it would probably help the science
of biology if the word ‘reversion’ and the ideas which it
denotes were wholly dropped, at all events until variation
has been studied much more fully than it has yet been.”*
He also says that to adopt the reversion hypothesis to
explain the discontinuous occurrence of new forms possess-
ing much perfection and completeness is inadmissible,
because of the frequent occurrence by discontinuous varia-
tion of forms which, though equally perfect, cannot all be
ancestral.

There is probably much truth in what Bateson says.
Reversion may have been credited with results which
could be sufficiently accounted for by variation. I have no
means of knowing whether Bateson and others who have
adversely criticised the reversion hypothesis, would account

themselves,”

* * Materials for the Study of Variation,’ 1894.

'ELEGONY AND REVERSION. 127

for zebra hybrids differing from their striped parents by
discontinuous variation or not. As, however, reversion
towards a remote ancestor in the case of the Hquide at
least has not been proved—is probably not even sus-
ceptible of proof,—it is most desirable that we should
endeavour to learn as much as possible from zebra hybrids
for and against the reversion doctrine.

Theoretically, as already mentioned, the result of crossing
distinct varieties or species should be the production of an
intermediate form. This ideal result is seldom attained.
It seems, however, that, as Liebscher has shown, the ideal
result is sometimes practically reached, e. g. when the two
species of barley, Hordeum steudelli 2? and H. trifurca-
tum 8, are crossed, a hybrid is obtained which is as nearly
as possible intermediate between the two parent forms.*

But usually, as Darwin long ago pointed out, the cross-
bred offspring, instead of combining in equal proportions
the characters of the sire and dam, may radically differ
from the immediate ancestors and often closely resemble
known or supposed remote ancestors. By inbreeding, the
carriers of heredity or, let us say, the germ units respon-
sible for maintaining the distinctive characters of any
given race are fixed and it may be strengthened. Hence,
when two inbred and closely related forms are mated, the
offspring are likely to closely resemble their immediate
parents. In cross-breeding exactly the opposite holds
true; it is quite uncertain what the offspring will be
like, unless one of the parents is highly prepotent. For
example, if two closely related thoroughbreds are mated
the offspring will almost certainly resemble the parents or
the grandparents—the resemblance being greatest to the
most inbred parent. But if a thoroughbred is mated with
a cross-bred mare—with, say, a country-bred Indian mare—
it is impossible to say what the progeny will be like; it may
be large but quite devoid of quality, or small and fine,
have plenty of quality but no substance. By inbreeding
and by a form of selective breeding (which though quite a

* Liebscher’s work is referred to in Weismann’s ‘ Germ-plasm,’ p. 301.

128 TELEGONY AND REVERSION.

different thing may lead to similar results), new strains may
be rapidly produced. Certain well-fixed types of Shetland
ponies have been formed by close inbreeding, and similar
results might be obtained without the disadvantages which
follow inbreeding by judicious selective breeding. For
example, if an English thoroughbred mare is mated with a
thoroughbred horse whose ancestors for some generations
have lived a comparatively natural life—in say Australia or
America,—a horse, nevertheless, closely resembling the mare
both in his physical and mental characters, the offspring
would in all probability present all the striking peculiarities
of the pareuts without any weakening of the constitution
such as is apt to follow in and in breeding. But as allow-
ance must always be made for variation (especially when
forms from widely separated areas are mated), for the
appearance of sports in one direction or another, the
offspring might very well be an improvement on the
parents—give evidence, in fact, of progressive develop-
ment in some useful or desired direction. We often use
the phrase “like produces like,” but we often fail to
realise that to give the offspring a chance of being like
the parents, the parents or their grandparents must be
like each other. It seems to me that, as a rule, progress in
any given direction, 7. e. progressive development, will
only be possible when the parents closely agree with each
other in their physical and mental peculiarities. They are,
of course, likely to agree when closely related by birth, if
their ancestors have been interbred for several genera-
tions ; but they may also agree in all essential points when
distantly related, or when belonging to quite distinct
strains,

The opposite of mating closely related forms is the
crossing of distinct breeds. ‘The result of intercrossing is
well known. We are all familiar with the phrase “the
swamping effects of intercrossing,” which implies that
quite the opposite result is obtained from what we arrive
at by isolation or inbreeding. Intercrossing, in fact,
generally tends to arrest. development in any given

TELEGONY AND REVERSION. 129

direction, to prevent the formation of new types or
varieties ; and hence, unlike inbreeding, it may be con-
sidered retrogressive in its tendency, and at the same time
uncertain in its results. If the intercrossing of varieties
in the same area arrests the formation of new species, is
non-progressive, if not actually retrogressive, the crossing
of distinct species from, it may be, widely separated areas
will, @ priori, not only arrest progressive development—
abruptly put an end to the progress the respective species
were making in various directions,—but actually lead to
retrogressive changes, in other words, to reversion. The
difference between breeding with almost identical inbred
members of the same variety and with representatives
(neither of them inbred) of two distinct varieties, may be
made more evident by an example from amongst the
pigeons. If two inbred fantails which present almost
identical characters are mated, the offspring will in all
probability agree closely with the parents, they may even
show some advance in the direction desired by the fancier
—in, say, the characteristic attitude or in the number of
feathers in the tail. If, however, one of these fantails is
afterwards mated with, say, a blue pouter, the young
instead of being intermediate between a fantail and a
pouter, may closely resemble the wild rock pigeon—may, in
fact, have reverted towards the remote ancestor. This
would simply be an exaggerated example of the swamp-
ing effects of intercrossing. If, therefore, the result of
crossing extreme forms is, under ordinary circumstances,
accompanied with retrogressive changes, I fail to see how
the difference in the markings of Romulus from those of
his sire could be considered as due to abrupt or discon-
tinuous variation.

If in Romulus we have a new creation—a decidedly
new variety rather than an attempt at the restoration of a
lost ancestor—it is remarkable that he should so forcibly
suggest in many ways the Somali zebra, and still more
remarkable that he should in the plan of his markings not
only agree with this year’s crop of hybrids, but also with

9

130 TELEGONY AND REVERSION,

hybrids between zebra mares and various breeds of horses
and to a considerable extent with zebra-ass hybrids.

If the result of crossing a blue pouter with four or five
different recognised varieties of pigeons invariably resulted
in the production of young resembling the blue rock, we
should unhesitatingly account for this by the reversion
hypothesis. If, on the other hand, the crossing led to new
and quite distinct types that bred true, we should in time
look upon these cross-bred forms as new varieties. In the
same way, if the result of crossing zebras with four or five
recognised species or varieties of the Hquide or horse
family leads to the production of hybrids all marked on
the same plan, we must, I think, admit that the resem-
blance is due in each case to reversion towards a remote—
it may be a common—ancestor.

But if it is difficult to imagine how by discontinuous
variation Romulus (with his numerous complete and perfect
stripes on the face, neck, and body, and rudiments of
stripes over the hind quarters) could be derived from a
Burchell’s zebra or an unstriped black mare, it will be
found still more difficult to understand some of the mark-
ings in this year’s hybrids. The new hybrids all differ
from each other and from Romulus. Yet in no respect
can they be said to present characters new to the Equide ;
there is no evidence in any instance of new departures or
of progressive development. The oldest (Remus), having a
three parts bred bay Irish mare for his dam, though much
lighter than the yearling, is marked in exactly the same
way, but he possesses callosities (chestnuts) on the hind
as well as the fore-legs, and his mane is as short and up-
right as in his zebra sire. About the next oldest (Heckla)
there is nothing remarkable save that the body colour is
already very dark. The dam is a skewbald (yellow and
white) Iceland pony with white mane and tail. I expected
her hybrid foal to be almost as light as a zebra, but instead
the stripes are indistinct and the spaces between them
mostly of a dark brown colour, while the mane and tail are
nearly black. The hybrid of a small black Shetland pony

TELEGONY AND REVERSION. - * 131

—in some respects a small edition of Mulatto—is especially
interesting. This hybrid filly suggests Romulus when at a
corresponding age, but she is smaller and more compact
and more self-assertive, but less docile. The general plan
of the striping and the coloration is the same as in Romulus;
and, as in Romulus, there are fourteen frontal arches (but
the pattern is somewhat different), and there are nine
vertical stripes across the body behind the shoulder stripe.
Over the hind quarters, instead of numerous more or less
transversely arranged spots, there have been from the first
numerous narrow somewhat zigzag bands. In other words,
unlike Romulus and the three other hybrids, in Norette
the croup and rump have been from birth decorated by
narrow transverse stripes such as we find on the Somali
zebra. But although there have been since birth numerous
distinct transverse narrow stripes extending well down the
hind quarters in the Shetland hybrid, this is no argument
in favour of discontinuous variation. In this case what
might be termed the Somali stage in the ancestral history
has been reached about a year sooner than was the case
with Romulus.

The fact that all the hybrids differ so decidedly in the
markings over the hind quarters from their common sire
while they agree more or less accurately with the Somali
zebra, seems to me to support the reversion hypothesis.
Further evidence in favour of reversion is afforded by
the neck stripes. Not very long ago, from a geological
point of view, there were two types of three-toed horses in
existence, one (Protohippus) in the New World, the other
(Hipparion) in both the New and the Old. Protohippus
was probably the ancestor of all our recent breeds of
horses ; Hipparion I look upon as the common ancestor of
the asses and zebras. The asses I believe parted com-
pany at an early stage with the zebras—before the zebras
had acquired their extravagantly striped coat. If asses
were never as fully and distinctly striped as horses, hybrids
between a common ass and a zebra might very well in their
markings present a simpler and more primitive arrange-

132 TELEGONY AND REVERSION.

ment than hybrids between zebras and horses, more espe-
cially at points where in horses the stripes long persisted.
Judging from the markings of my zebra hybrids, it might
have been predicted that crosses between an ass and a
zebra would present numerous irregularly arranged spots
over the hind quarters, and numerous ill-defined wavy
lines on the neck and on the sides of the body.

As a matter of fact, there is preserved in the Natural
History Museum, South Kensington, a hybrid said to be
between a common zebra and a common ass, which is pro-
fusely spotted over the hind quarters, and marked by ill-
defined stripes on the neck and body. This hybrid has,
as might have been expected, a distinct dorsal band, distinct
shoulder stripes, and well-defined transverse bars across
the legs.

If in these hybrids we have a more primitive form of
marking than is ordinarily found in zebra-horse hybrids,
it is conceivable that in some of my hybrids a more
primitive arrangement of the stripes might be met with
than occurs in Romulus; that as the mares belong to
different breeds and colours, and differ in the extent of
their inbreeding, the reversion (if there is such a thing) is
likely to be more marked in some of the offspring than in
others. I have already pointed out that though there
are only twelve cervical stripes in Matopo (the sire of the
hybrids), there are, when the shadow stripes are included,
over twenty im a Transvaal filly and twenty-four in
Romulus. In the British Museum zebra-ass hybrid there
are numerous stripes which, because of their branching
and blending with each other, cannot be easily numbered.
In the Shetland hybrid there is an intermediate condition
of the neck stripes. Twenty-four stripes, as in Romulus,
have been differentiated, but a number of indistinct stripes
—like the shadow stripes in the zebra filly—occupy the
intermediate spaces. That these narrow obscure stripes
are the vestiges of never very distinct ancestral stripes,
and that they correspond to some of the wavy lines in the
zebra-ass hybrid, seems to me extremely probable. But

T'ELEGONY AND REVERSION. 133

similar “ shadow ”

stripes also occur in a small bay Clydes-
dale mare’s hybrid; only in this case obscure stripes are
found between the vertical body stripes as well as on the
neck. It is almost inconceivable that by variation there
could be produced in a single generation not only what
seems to be the typical number of neck and body stripes
for a zebra-horse hybrid, but also shadow stripes, i.e.
markings which mimic stripes in process of disappearing
in some of the living zebras. By the reversion hypo-
theses their presence is easily understood, but to account
for them by saying they are the result of abrupt or dis-
continuous variation seems to me to be alike unnecessary
and illogical. Taking into consideration all the facts above
enumerated, I am strongly inclined to the view that in
Romulus and this year’s crop of hybrids we have not new
and striking variations, but more or less accurate restora-
tions of certain remote ancestors, or an attempt to create
the hypothetical “ mid-parent” of the remote ancestry ;
in other words, we have strong evidence that under certain
circumstances quite as pronounced reversion occurs in the
Equide as in pigeons.

It thus appears that when the colour and markings of
Norwegian and other ponies are considered, the conclusion
seems warranted ‘that all the different breeds of horses
have descended from yellowish-brown hog-maned ances-
tors, striped somewhat after the fashion of the mountain
zebra (Hquus zebra). Further, by taking into considera-
tion the plan of the striping in the various living zebras,
it may be inferred that of all the recent varieties and
species the Somali zebra is in many respects the most
primitive in the pattern of its decoration. It has also been
shown that the five zebra hybrids already bred neither
resemble their common sire, nor agree in their markings
with Norwegian and other ponies, nor yet stand midway
in colour, marking, &c., between their immediate ancestors.
When due allowance is made for inbreeding in the respec-
tive dams, the conclusion seems inevitable that the remark-
able differences between the hybrids and their immediate

134 'ELEGONY AND REVERSION.

ancestors are due to reversion, either towards the less
remote ancestors of the zebras or horses, or towards the
common ancestors of all the recent Equide.* In considering
the question, Were the ancestors of the horse striped?
it has been incidentally shown that all foals do not pass
through a striped stage, and that many foals have stripes
at birth which ordinarily completely or all but completely
disappear. That foals are usually of a bay or dun colour,
and frequently striped at birth, seems to be best accounted
for by saying they wear for a time their ancestral colours,
either owing to the influence of simple heredity, or to an
extraordinary kind of heredity, commonly known as atavism
or reversion. It has been especially shown that the greater
the differeuce between the sire and the dam, the greater
the reversion is likely to be; and, it may be added, the
longer are the ancestral markings likely to be retained.
For example, hybrids between two distinct species usually
resemble the remote ancestors more than crosses between
two varieties or races, and while cross-bred forms (crosses
between closely allied races or varieties) may soon lose any
hints they may have of remote ancestors at birth, hybrids
generally retain the ancestral characters throughout life.

The Nature of Telegony.

Having considered the question, Were the ancestors of
the horse striped? and the still more important question,
Does reversion occur in the Equide? we are now in a
position to deal more effectively with the telegony problem,
as far as the horse family is concerned. It will be evident
that by assuming horses have descended from striped
ancestors, and that the less remote ancestors sometimes
still reassert themselves, that by what we term atavism or
reversion horses even now sometimes wear the ancestral
colours, it will be evident that by granting these premises
the question has been enormously complicated.

* Or to use Mr. Galton’s phraseology, the hybrids have reverted so as

to resemble the hypothetical “ midparent,” uniting the characters of their
respective remote ancestors.

TELEGONY AND REVERSION. 135

Lord Morton and his followers believed the Arab mare
had been “infected,” because her subsequent progeny to a
black Arab horse had stripes and a more or less upright
mane. If, however, purely-bred horses have sometimes a
hog-mane and as many stripes as the Gore Ouseley “ colts,”
how is it possible to prove that “infection” has occurred
in any given instance? ‘To take a concrete case, to what
extent would Mulatto’s second foal require to differ from
an ordinary foal in order to prove “infection” has taken
place? and, more especially, will the telegonous foal
require to resemble Matopo (the previous sire) or one of
Mulatto’s or Matopo’s less remote ancestors ?

Hitherto experimenters seem to have invariably looked
for some resemblance to the previous sire in the pure-bred
subsequent offspring, and to have neglected or considered
worthless resemblances to remote ancestors. The late Sir
Everett Millais (who, as already mentioned, made all sorts
of experiments during a breeding experience of nearly
thirty years’ standing, and made over fifty special experi-
ments to induce a case of, telegony for Mr. Romanes)
records what he considered a perfectly authentic instance
of telegony.* In this case a pure-bred fox terrier “ was
spotted exactly like a Dalmatian.” The litter previous to
the one in which the spotted fox terrier appeared was
sired by a Dalmatian, and hence it was inferred that “ in-
fection ” had taken place, the result being in this case a
striking resemblance on the part of the subsequent off-
spring to the previous sire.

At a meeting of the Zoological Society held on No-
vember 17th, 1896, “Mr. Chalmers Mitchell exhibited
and made remarks on a supposed case of telegony as
shown by a fox terrier whose mother, a pure fox terrier,
had previously bred some mongrel dachshunds.” Sir
Everett Millais “denied that the specimen exhibited any
trace of the influence of the dachshund sire of the previous
litter, and traced the divergences of the puppy from the
modern fox terrier type to the original source of the

* ©T'wo Problems of Reproduction,’ p. 20.

136 TELEGONY AND REVERSION.

breed.” * In other words, Sir Everett was evidently not
prepared to admit that ‘ infection ” might lead to the subse-
quent progeny resembling a remote ancestor—“ the original
source of the breed.”

In support of my statement that the previous sire has
been hitherto taken as the standard for comparison rather
than a remote ancestor, the following cases may be cited:

(a) A black and white sow which had offspring to a
chestnut-coloured wild boar had afterwards a litter to a
boar of her own breed, some of which were marked with
chestnut. t

(b) A dachshund which had a litter to a sheep-dog had
afterwards pups to a pure dachshund; the second and third
years’ produce resembled the sheep-dog as much as the
dachshund sire.f

(c) An ordinary cat had kittens to a tailless Manx cat,
and then to a cat of her own kind; several of the second
litter of kittens were tailless.§

(d) “ Blair Athol,” a blaze-faced chestnut horse, accord-
ing to various writers “infected” the mares that bred to
him, with the result that some of these inares produced
Blair Athol like foals to “Wild Oats ””—“ the last horse
in the world to get stock of a similar stamp,” 7. e. to get
Blair Athol like foals. ||

If a telegonous foal resembled, as has generally been
assumed, the previous sire, while an atavistic foal of neces-
sity takes after a more or less remote ancestor, it would
be comparatively easy in many cases to say whether in-
fection had taken place, to decide on the lines adopted by
Sir Everett Millais in the case of Mr. Chalmers Mitchell’s
fox terrier. If, on the other hand, the result of “ infee-
tion ” is identical as far as it goes with the result of rever-

* The Field, Nov. 28th, 1896.

+ ‘Phil. Trans. Roy. Soc.,’ 1821, p. 21.

{ Herbert Spencer, Contemp. Review, May, 1893.

§ Journ. des Débats, Sept. 9th, 1897. :

|| The Sportsman, Jan. 3rd and Feb. 29th, 1896, letters by the ** Special
Conimissioner.”’

TELEGONY AND REVERSION. 137

sion, coming to a definite conclusion will be difficult—will
seem, in fact, to some next to impossible.

I had not intended to consider at this stage the possible
causes of telegony, but as the result of “infection” (if it
occurs) will depend more or less on the method by which
it is produced—in other words, as the mode of “ infection”
may determine whether the subsequent offspring resemble
the previous sire or a remote ancestor, it is desirable to
refer briefly to some of the suggested explanations of the
supposed phenomenon.

Sir Everard Home believed Lord Morton’s mare pro-
duced striped foals to the black Arab horse because her
first mate—the quagga—had produced a profound and
lasting impression on her nervous system ; that she, as it
were, had never quite succeeded in getting the quagga
out of her mind. Sir Everard tells us he considered the
markings on the subsequent offspring of Lord Morton’s
mare as ‘fone of the strongest proofs of the effect of the
mind of the mother upon her young that has ever been re-
corded.”’* If telegony is due to mental impressions, as
Sir Everard Home and many others since his day have
believed, the subsequent progeny might very well resemble
(I might almost say ought to resemble) the previous sire,
and not a remote ancestor. But although it is widely and
firmly believed that the offspring may be influenced through
“¢the mind of the mother,” Sir Everard Home’s is the least
likely of all the explanations hitherto suggested.

Mr. Herbert Spencer believes telegony is due to a kind
of pangenesis, that ‘ while the reproductive cells multiply
and arrange themselves during the evolution [develop-
ment] of the embryo, some of their germ-plasm passes into
the ... parental body,” to eventually reach and be after-
wards included in the reproductive cells subsequently
formed.t This explanation has found favour with not a
few physiologists in the past, and is still seriously con-
sidered. But even granting the possibility of this indirect

* «Home Lectures on Comparative Anatomy,’ vol. iii, p. 307, 1823.
| Contemporary Review, March, 1893.

138 TELEGONY AND REVERSION.

mode of reaching and infecting developing (maturing)
reproductive cells, it by no means follows the offspring
resulting from these cells will resemble the previous sire.
All that could be safely asserted is that the subsequent
offspring would resemble the previous offspring, or the
ancestors of the immediate parents. If, for example,
Mulatto’s germ-plasm was indirectly infected by germ-
plasm from her first foal during its development, her
second foal to the Arab horse (granting telegony is true)
should more or less resemble her first foal (Romulus), or
one of her remote ancestors, rather than her first mate
Matopo.

Professor Weismann thinks telegony (if it occurs) is best
accounted for by supposing that some of the germ-plasm
of the first sire reaches and penetrates some of the imma-
ture ova as well as the mature one from which the first
embryo is developed.* This germ-plasm, instead of merely
serving as so much nourishment to these immature ova,
according to this view retains its independence and event-
ually asserts its influence on the future progeny to a second
and different sire. This may be better understood by an
example. If any given simple unicellular organism were
to devour another but smaller organism belonging to a
different variety or species, and then unite with one of its
own species, when division eventually took place the new
individuals would (supposing the comparison to hold) pre-
sent some of the characters of the species originally devoured
as food. Although it is difficult to understand how an egg
could incorporate germ-plasm in this way while still in pro-
cess of maturing, and still more difficult to understand how
this incorporated germ-plasm could retain for an indefinite
time its independent existence (play the part, as it were,
of an encysted cellular parasite, which at the right moment
wakes up and insists on being represented in the future off-
spring), this explanation, regardless of the fact that vestiges
of male germ-cells have never been seen in immature ova,

* Weismann, ‘The Germ-plasm.’

TELEGONY AND REVERSION. 139

will evidently be very generally adopted should telegony be
eventually raised to the rank of a fact.*

If telegony is due to the direct “ infection ” of the germ-
plasm of the dam by the germ-plasm of the first or of a
previous sire, there seems no escape from the conclusion
that the subsequent progeny should resemble the first
offspring rather than the previous sire. In the case of
Mulatto, her second foal (to the Arab horse) should, if
infected, resemble her first hybrid foal Romulus. I have
already pointed out at considerable length that Romulus
is surprisingly unlike his Burchell zebra sire, and I have
given reasons for the belief that he takes after the Somali
zebra, probably the most primitive of all the living striped
horses. Hence, if there are stripes in Mulatto’s second
foal, it might be argued they should of necessity agree
with the stripes in Romulus or in the Somali zebra or in
some of Mulatto’s ancestors.

In other words, the result of “Infection,” according to the
generally accepted (and it must be confessed most feasible)
explanation, should as far as it goes be identical with
“ Reversion.” It was in anticipation of this conclusion that
I was led to discuss so fully striping and reversion in the
Equide, and to consider experiments with dogs at the out-
set of comparatively little value seeing we know so little of
the dog’s ancestors. But if the developing ova are capable
of incorporating rather than assimilating germ-plasm after
the manner suggested by Weismann and Romanes, why is
telegony so extremely rare ?—according to Romanes only
occurring in one or two per cent. of cases; according to
Sir Everett Millais not only exceedingly rare but abnormal.

Three reasons occur to me why telegony, if possible,
happens or rather appears to happen but rarely. In the
first place, the germ-plasm of the previous sire may only
be able to obtain a footing in ova at a certain stage of
ripeness. If germ-plasm (of the first sire) enters eggs

* Mr. Heape evidently believes that if telegony occurs, the characteristics

of the first sire can only be transmitted to the offspring of the second
through the germ-plasm of the dam.—Wature, Dec. 30th, 1897, p. 215.

140 'ELEGONY AND REVERSION.

before a certain stage in the process of maturation isreached,
it may serve as so much nourishment, and thus fail to assert
itself in the subsequent progeny ; whereas if it enters later
it may obtain a footing, reach the nucleus, and eventually
take part in the formation of the subsequent offspring. In
the second place, the whole or almost the whole of the
incorporated germ-plasm of the previous sire may some-
times be discharged in the polar bodies, t.e. when the
nucleus of the all but ripe egg is discharging the half of
its germ-plasm. Were this to happen the ‘‘ infection”
would either not take place at all or be so hmited that it
might readily escape notice. In the third place, telegony
may seem to be rare because of the prepotency of the sub-
sequent sire. The first two explanations are at the best
mere guesses, but the third may be a very real explana-
tion.

It is well known that some breeds are so fixed that they
almost invariably produce offspring like themselves, how-
ever they happen to be mated. For example, while the
black Galloway polled cattle almost invariably throw blue-
greys to white shorthorn bulls, they frequently yield to
other breeds offspring so like themselves that even experts
are at times deceived. For example, “ Twenty years ago
the late Duke of Buccleuch, K.G., tried the experiment of
mating Galloway bulls with West Highland heifers. The
bulls he used were Baron Douglas (614) and Border Chief ~
of Drumlanrig (1015). The females were superior West
Highland heifers, one of which, I understand, was bred by
Mr. Stewart, of Ensay, and the other by Lord Malcolm, of
Poltalloch. When the produce—two heifers—were grazing,
at the age of about eighteen months, among a lot of nearly
a score of pure-bred pedigree Galloway heifers, half a
dozen of the most experienced and best known breeders
of Galloways were asked by his grace’s manager to pick out
the Galloway-Highland crosses from among the pure ones,
and each of these experienced judges picked out the
wrong animals, so closely did the half-breeds in every

TELEGONY AND REVERSION. 141

particular resemble the pure ones.”* Mulatto’s hybrid
Romulus might hence have been the image of his gaudily
painted sire Matopo. It is even conceivable Romulus
might have closely resembled his almost jet-black dam.
When hybrids or cross-bred offspring are identical or
nearly identical with the first sire, the “infected”? sub-
sequent offspring (telegony being taken for granted) might
also resemble the first sire. Isay might advisedly, because

Fic. 40.

Mulatto.

if the second sire happened to be distinctly inbred, or for
some other reason extremely prepotent, the influence of
the dam, plus the influence of the first sire, might be com-
pletely overcome, with the result that the subsequent
progeny would very closely resemble the second sire.

It thus appears that the further the telegony problem is

* From a letter by the Rev. John Gillespie, LL.D., president of the
Highland and Agricultural Society, the Field, January Ist, 1898.

142 TELEGONY AND REVERSION.

considered the more complicated it becomes. But not
only has inbreeding to be taken into consideration, the
fact already insisted on must also be borne in mind, viz.
that pure-bred foals are occasionally striped; in other
words, that the result of “infection” on the subsequent
progeny by a zebra sire may be identical or almost identical
with simple reversion.

If infection is not only possible but constant, it follows

from what has already been said that the telegonous off-

spring might either (1) resemble* a remote ancestor, or (2)

* Tt should be borne in mind that any part of an animal may be
“infected ;”? that in the case of foals evidence of infection may be found
in, e.g., the hoofs, though not in the warts ; in the structure, though not
in the colour of the hair; in the movements and habits, though not, as far
as the eye can detect, in the muscles or nervous system. Hitherto atten-
tion has been mainly directed to the colour of the hair and feathers in
experiments bearing on reversion—hardly at all to the general structure
and habits. That crossing of somewhat extreme forms affects the nervous
system, the muscles, and skeleton, as well as the colour and form of the
skin and its appendages, hair, feathers, hoofs, &c., is extremely probable.
Last summer a small dark bantam hatched out nine chicks, three of
which were by a large Indian game cock having some Dorking blood in
his veins. Of the three cross-bred chicks the two survivors might now
be almost taken for jungle fowl, the cock only differing from some pure-
bred birds I saw recently at Achnamara, in Argyllshire, in having a double
comb and comparatively few dark hackles on the breast. But what is
perhaps more remarkable, the birds resembling jungle fowl in size and
colour differ from the others in their habits. For example, when
suddenly disturbed they fly off, sometimes for a considerable distance,
evidently in a state of great alarm; while the other members of the same
brood either take little notice of the intruder, or simply run under a
hedge or whatever cover may be available. McKenny Hughes, in his
memoir* on ‘ British Breeds of Cattle,” refers to numerous horn-cores
found in ancient ditches (twelfth to fifteenth century) cleared out for the
foundations of the University Press and other buildings in Cambridge
during the years 1892-3. Of over 125 horn-cores “there were none that
could be referred to a long-horned breed, and few that showed any traces
of Roman type.” After carefully considering the matter, McKenny
Hughes came to the conclusion that these horn-cores afforded evidence of
the existence of a mixed breed in the act of “ reverting sporadically to
various primeval types, but principally to the numerically predominating
Bos longifrons,” i.e. to the small ancient British (Celtic) shorthorns.

* © Archeelogia,’ vol. lv, pp. 125—158.

TELEGONY AND REVERSION. 143

the previous sire, or (3) the subsequent sire, or (4) the dam.
From the fact that Romulus resembles the Somali zebra,
Mulatto’s second foal should also, though only to a limited
extent, resemble the Somali zebra,—or, which is the same
thing, somewhat resemble Romulus. Had Matopo been
inbred and more prepotent than Mulatto, then Romulus
would in all probability have resembled Matopo. If, con-
versely, Mulatto had been inbred and more prepotent
than Matopo, Romulus would most likely have resembled
Mulatto. Mulatto’s second foal, if to a non-prepotent sire,
should resemble Romulus; but if to an inbred prepotent
sire, the second foal ought rather to resemble the second
sire. If, however, the second sire belongs to a different
breed from Mulatto,—if there is a certain amount of
antagonism between the germ-plasms,—the second foal
may revert, and resemble one of the less remote ancestors*
of the true horses. It would obviously be impossible or
all but impossible to distinguish this form of reversion—
reversion resulting from crossing two distinct breeds—
from reversion due to infection by a previous sire. There
is still another possible, it may be a highly probable,
result. The influence of the previous sire may be so

* Many who believe telegony occurs in mammals seem to think it is im-
possible in birds. If telegony is due to indirect “infection,” to germ-
plasm proceeding from the developing embryo by a roundabout road to
ova in process of maturing, one can understand why in birds it is impos-
sible. If, however, the germ-plasm of the first sire passes directly to the
immature eggs, there is no reason why there should not be telegonous
birds as well as telegonous mammals. Sir Everett Millais experimented
with ducks, hens, and pigeons, without obtaining any evidence of telegony.
If, however, he only looked for a resemblance to the previous sire, or if the
subsequent sires were highly inbred, cases of infection may have been over-
looked or obscured. For example, if a white fantail hen is first bred with
a blue pouter and next with a white fantail, one of two things might,
happen,—the offspring to the second mate (the white fantail) might be iden-
tical with their parents (if they happened to be inbred), or suggestive of a
blue rock pigeon. If the latter result happened, it would be considered by
some a case of reversion, regardless of the fact that the first cross between
a white fantail and a blue pouter might (through the influence of reversion)
resemble not a pouter but a rock pigeon.

144 TELEGONY AND REVERSION.

feeble that, instead of leading to a reversion towards the
hypothetical ‘ mid-parent” of the remote ancestry — that
is, to offspring combining to a limited extent the characters
of the ancestors of both the horses and the zebras,—it may
only set up sufficient disturbance in the reproductive sys-
tem of the dam to lead to a slight regression towards her
own particular and not very remote ancestors.

Before describing Mulatto’s second foal, the question
may be asked, what amount of striping or other changes
would be required to conclusively prove she has been
“infected” by the zebra? Obviously if the germ-plasm
of the first sire unites with a maturing egg, the previous
sire could only enter into the formation of the second foal
to a very limited extent. According to Mr. Galton’s law
of ancestral heredity, the two parents contribute one half,
the four grandparents one fourth, the eight great-grand-
parents one eighth, and so on, to the total heritage of the
average offspring. If this law holds it follows that the
male parent only contributes one fourth of the total heri-
tage. If the previous sire contributed equally with the
reputed sire, the proportion would be one eighth for
each. But even if we admit that an immature egg may
contain the whole of the male germ-cell of a previous sire,
i.e. one eighth, this would be halved during the “ re-
ducing division” of the nucleus; hence, at the most, the
contribution of the previous sire would be one sixteenth,
but actually (supposing there is direct “infection” of
the ovum) in the vast majority of cases considerably less.
Further, the half not contributed by the parents would
be mainly provided by the ancestors of the dam. Hence,
when the most liberal allowance is made, the previous sire
could only under ordinary circumstances enter to a very
limited extent into the subsequent offspring. It is true
that the colt and filly bred by Sir Gore Ouseley from Lord
Morton’s mare were more richly striped than the quagea
hybrid. This has always seemed to me to prove that the
majority of the stripes in the Gore Ouseley “ colts”? were
inherited directly from the black Arabian.

TELEGONY AND REVERSION. 145

Mr. Wilfrid Blunt believes that the offspring of white
Arabs are apt to show stripes; while Herr W. von Nathusins,
in a recent letter, indicates that he thinks there are latent
stripes in black horses. From what I have seen of black
horses when in the act of shedding their winter coat, I
think one may go further than Nathusius and say that
stripes sometimes actually exist in black or all but black
horses. Supposing there is no such thing as telegony,
and that white and black horses tend to produce striped
offspring, and, further, that when fairly distinct types are
crossed the offspring are likely to revert, what extent of
striping might be expected in the foal of a black Island
of Rum pony which has never bred with a zebra, and a
grey Arab horse ?

Darwin tells us he “ never heard of either shoulder or
leg stripes without the spinal stripe. The latter is by far
the commonest, as might have been expected as it charac-
terises the other seven or eight species of the genus.”*
This has also been my experience, and, as far as I know, it
has been the experience of all who have directed their
attention to the subject. Hence Mulatto’s second foal
(even if there is no such thing as telegony) might have a
dorsal band, shoulder and lee stripes, and a number of
not very distinct stripes on the face, neck, and body.
We still know too little of the plan of the stripes in the
ancestors of the horse to admit of their being compared
with the stripes in the zebras ; what has been ascertained,
however, points to the arrangement differing considerably.
The shoulder and leg stripes so common in the domestic
ass may be said to be transmitted almost unaltered to
zebra-ass hybrids. There is, however, no evidence that
any stripes are derived directly from the horse in zebra-
horse hybrids; it looks as if the stripes of the ancestors of
Mulatto had been overcome or masked by stripes charac-
teristic of the ancestors of the zebras.

The likelihood of stripes in addition to shoulder and leg
stripes and a dorsal band occurring in a foal bred from an

* © Animals and Plants,’ vol. i, p. 63.

10

146 TELEGONY AND REVERSION.

Island of Rum pony and a grey Arab is extremely small.
The probability, e.g., of croup stripes appearing is not
great, for though in some foals the hair across the croup
forms wavy bands, stripes in this position are extremely
rare. I am not forgetting that Mr. Darwin bred a foal

Fie. 41.

Benazrek.

marked with numerous narrow stripes acréss the croup ; but
in the absence of a figure it is impossible to say whether
these narrow stripes were comparable to the stripes found
in say the Somali zebra, or in some of my zebra hybrids.
Hence, as already said, the probability of an Island of

TELEGONY AND REVERSION. 147

Rum pony which had not been crossed with a zebra
producing a colt striped over the croup is not very great.

Mutatto’s Second Foal.

The second foal of Mulatto was born on the 16th July,
1897, the period of gestation being 330 days—twelve days
shorter than in the case of Romulus. The dam (Mulatto,
Fig. 40) has already been sufficiently described. The sire
(Benazrek, Fig. 41), bred by the late Harl of Warwick, is
a grey Arab, a son of Azrek, for some time a member of
Mr. Wilfrid Scawen Blunt’s famous stud at Crabbet Park,
Sussex. Azrek, also a grey, belonged to the ancient
Seglawi Jedran family. Benazrek’s dam (Shemptes) was
also originally a grey ; now she is almost white. I have
had under observation for some time three ‘‘colts”’ by
Benazrek. One, having a well-bred bay mare for her
dam, was of a reddish dun colour at birth, with a blaze.
This ‘colt ” (now—1898—rising three) will ultimately be
grey like hersire. Even at birth there were no indications
of stripes. A second foal by Benazrek (also rising three)
had for her dam a dark grey thoroughbred Irish pony.
This foal was at birth of a dull chestnut colour, but now
she isa dark grey not unlike her dam. Like the above-
mentioned foal, this filly has never shown any stripes.
Benazrek’s third foal (born May 30th, 1897) has for her
dam a flea-bitten 13 hands New Forest pony, in which
there may very well be a trace of Arab blood.

This pony had a mule foal (Fig. 42) to a Forest donkey
in 1895, but missed having a foal in 1896. At birth her
foal to Benazrek was of a reddish dun colour; when three
months old the foal was of a light grey colour; at eight
months a dark grey, with a blaze anda small reddish patch
near the left nostril. This foal when a few days old had a
number of stripes. There was a distinct dorsal band, a
stripe nearly two inches in width across the withers in the
position of the shoulder stripe in the common ass, and in
front of this on each side of the neck two narrow cervical
stripes. There were also three faint vertical stripes extend-

148 'ELEGONY AND REVERSION.

ing downwards from behind the withers to a short obscure
ventral band; further, there were obscure bars above the
knee and hock, and across the chest and the upper part of
the forearm. When a month old the leg stripes were no
longer visible; when two months old the neck stripes
had vanished and only a vestige of the shoulder stripe
was left; but even at three months the vertical stripes
extending down behind the elbow were quite evident.

Fic. 42.

Mule. Dam a flea-bitten New Forest pony.

Only an indistinct dorsal band now remains. Whether
these stripes are due to the previous sire being a donkey
it is difficult to decide. In favour of the view that the
Forest pony has been infected by the previous but by no
means first mate are two facts worth mentioning. I have
already given reasons for the belief that in iis remote
ancestors of the horse long hairs were confined to the lower
part of the tail, and that it is only during comparatively

TELEGONY AND REVERSION. 149

vecent times that long hairs have extended up to near the
root. It is known to many that in most horses the hairs
from the upper two or three inches of the tail are shed
with the winter coat. But the shedding in the vast
majority of cases is so gradual, and the growth of the new
hair so rapid, that the loss of the dead hairs is hardly per-
ceptible. In the mule, on the other hand, the long hairs
from about six inches of the root of the tail are usually
shed so rapidly that only a covering of comparatively short
hair is left. My zebrules agree with ordinary mules in
this respect, but the shedding of the long hairs may be
more extensive, only the long hairs springing from the
lower third of the dock persisting. In Hyla, the Forest
pony’s 1897 foal, all the long hairs of the upper 24 inches
of the tail were shed during April and May (1898), leaving
the base of the dock almost bare. In the sire and dam of
Hyla the hairs are shed very gradually from the root of
the tail—a casual observer would never notice that the old
hairs are being slowly replaced by new. The other fact is
that the wart (chestnut) is absent from the left hind leg.
Warts have never, as far as I am aware, been found on
the hind legs of asses or zebras, and they are generally
believed to be invariably absent from the hind legs of
mules. But they are also said to be sometimes absent
from the hind legs of horses. In the Forest mule (Fig. 42,
Hyla’s half-sister) warts, as it happens, are present; or, to
be more accurate, there are small, smooth, bare spots in the
position of warts. In all probability many mules have
vestiges of warts, and it is just possible that in horses said
to be without warts there may be similar vestiges. In one
of my zebrules there is a small wart on one of the hind
legs. The absence in Hyla of a wart from one of the hind
legs, the falling out of the hair from the root of the tail,
and the presence of faint indications of stripes across the
croup, may be looked upon as mere accidental coincidences,
or as the result of simple reversion ; but, on the other hand,
these unusual conditions may be due to “ infection ”—to,
let us say, some of the germ-plasm of the previous sire

150 ''WLEGONY AND REVERSION.

(the Forest donkey) having asserted its influence more

particularly in the tail, warts, and hind quarters.
Mulatto’s second foal, when seen in bright sunshine half

an hour after birth, seemed to be quite devoid of stripes.

Fic. 48.

Mulatto’s Second Foal.

When, however, the foal was carefully examined in a
suitable light, numerous stripes revealed themselves. The
foal was of a dark bay, in some parts almost of a brown
colour, and as the majority of the stripes were only a shade
darker than the rest of the coat, they were, except in a

TELEGONY AND REVERSION. 151

favorable light, difficult to see and almost impossible to
photograph. When a week old Mr. Edwin Alexander*
was kind enough to fill in the more important stripes in.
an outline sketch, a photograph of which is reproduced
in Fig. 43. I carefully compared the sketch with the
foal, and had .no difficulty in making out all the stripes
shown in the figure. While some of the stripes were
quite distinct to the eyes of even unskilled observers,
others were most subtle and only visible in certain lights.

Fic. 44.

Mulatto’s Second Foal.

Fig. 44 has been reproduced from a photograph taken
when the foal was ten days old.

In the zebra the hairs of the dark stripes and bands
are pigmented from root to tip. In Romulus the dark
hairs are as a rule only pigmented to within about half an
inch of their roots, whereas in Mulatto’s second foal there

* To Mr. Alexander, jun. (already noted for his accurate and beautiful
drawings of animals), I am greatly indebted for the sketch (Fig. 43) of
Mulatto’s second foal.

152 TELEGONY AND REVERSION.

was only a faint change of colour near the apex of the hairs
forming the indistinct stripes. If the stripes in this foal
are due to “infection,” the hairs forming them could
hardly be expected to be as deeply and extensively pig-
mented as in the half-zebra Romulus. As Fig. 43 shows,
there are cervical but no shoulder stripes, numerous
stripes on both the fore and hind legs, vertical stripes
across the body, oblique stripes across the loins, faint
stripes across the flank feather, and, most interesting
and important of all, transverse stripes across the croup.
[ have already mentioned that Darwin never found leg
stripes occurring in horses without the dorsal stripe, and
even in the striped colt he bred there was a trace of the
spinal stripe. In Mulatto’s second foal, however, no trace
of a dorsal stripe could ever be detected, ¢.c. one of the
oldest if not quite the oldest stripe in the Equide family was
not represented in this foal. The stripes on the neck and
the lower parts of the legs are not specially significant, but
the stripes between the elbow and the shoulder-joints and
ona level with the stifle are undoubtedly rare even in foals,
while numerous narrow stripes in the region of the loins
and stripes across the croup have, as far as I am aware,
only previously been observed in the foal bred by Darwin.

In Darwin’s foal, it will be remembered, “almost the
whole body was marked with very narrow dark stripes, in
most parts so obscure as to be visible only in certain
hghts, hke the stripes which may be seen on black kit-
tens.” These stripes were plainest on the forehead, where
they formed a set of pointed arches one under the other,
but they were also “ distinct on the hind quarters, where
they diverged from the spine and pointed a little for-
wards.” ‘This colt ultimately turned out brown, but when
““two or three months old all the stripes entirely disap-
peared,’’*

In the absence of a figure it is, unfortunately, impossible
to contrast the stripes described by Darwin with those in
Mulatto’s second foal. I may, however, point out that

* © Auimals and Plants,’ vol. i, 2nd edit., p. 60.

Q

TELEGONY AND REVERSION. 1538

narrow stripes or, to be more accurate, narrow ridges
(some of them over, some under, a quarter of an inch in
width) occur in all foals, more especially over the loins
and croup and in the vicinity of the flank feather. These
ridges are especially evident at birth in well-bred foals
having a fine coat.

When the finger is carried across these ridges, one is
tempted to conclude they are entirely or mainly due to
crumpling or wrinkling of the skin. I was led to suspect
they were not due to crumpling of the skin by noticing
how the hair was shed in an Irish bay mare (Biddy) and
in her yearling hybrid, Remus. In the latter, the spaces
between the stripes across the hind quarters first lost their
hair, with the result that the stripes projected freely for
some time above the surface. In the dam, the hair in the
vicinity of the flank feather was shed so as to leave a
number of narrow tracks having the same disposition as
the ridges in new-born foals. Eventually the hair forming
the tracks was shed, leaving a perfectly smooth coat.
Soon after noticing this I had sent me a well-bred foal
(which died when about a week old) showing the character-
istic ridges on the sides of the body as well as over the
croup, loins, and hind quarters. I succeeded in getting
the skin preserved without in any way altering the appear-
ance of the ridges in question. When this skin was held
up to the light, it was at once evident that the ridges were
not due to furrows in the skin, but to the presence of
tracks of long hair, separated from each other by narrow
spaces sparsely covered by short fine hair.

About the same time I had the opportunity of examining
twins* that had been born nearly two months before their
time. In one (the smaller) there were over the trunk
narrow tracks of long and relatively thick hairs, having
the same general direction as the hair in the adult. The
spaces between these tracks—on an average half an inch
in width—were occupied by short, fine, and almost invisible
hairs. In the larger twin, each track was wider but less

* Sire of twins a Clydesdale; dam a light cart-horse.

154 TELEGONY AND REVERSION,

evident, owing to the intermediate spaces being better
clothed.

The ridges in the young foal and the rows of relatively
long thick hairs in the footuses agree very closely, if not
absolutely, with the lines of moisture seen on a horse when
it begins to perspire, and with the lines followed by the
water after a light shower. Inthe prematurely born foals,
two phases in the evolution of the coat of the horse may
be represented; the least developed seems to point to a
time when there was but a sparse covering of hair, but yet
with the hair so arranged that it served to carry off the
rain as rapidly as possible along definite nes.

When the skin showing the narrow parallel ridges and
furrows is examined, the mane is seen to extend nearly to
a level with the flank feather. From the withers the hair
of the mane gets gradually shorter, but it runs in the
same direction and has the same structure as the hair
forming the mane in front of the withers. From the part
of the mane behind the withers, ridges quite a quarter of
an inch wide run downwards and slightly backwards over
the sides. Over the croup there is a smooth patch of hair
of a lozenge shape, measuring about six inches by one and
a half at the widest part—a patch corresponding to the
wide portion of the dorsal band in zebras and horses.
Irom the front part of the lozenge about fourteen narrow
ridges arch outwards and downwards in front of the
flank feather (Fig. 45); while from the back part equally
narrow ridgesarch backwards over the hind quarters—the
upper ones approaching each other as they proceed towards
the root of the tail. Filling up the space between these
two sets of ridges are others which spring from the flank
feather, some bending downwards in front, others behind,
the feather, towards the stifle. Fig. 45 indicates the
arrangement of the ridges around the upper end of the
right flank feather. Fig. 46 shows the appearance the hair
presents in the space immediately above the flank feather
(lying within the four circles shown in fig. 45) when the
skin is held up against the light. In a week-old cinnamon-

156 TELEGONY AND REVERSION.

coloured foal by a thoroughbred chestnut horse out of a
bay half-Arab mare, the flanks, croup, hind quarters, and
thigh are marked all over by very distinct ‘ narrow
stripes,” some of which appear of a different colour from
the intermediate spaces. But all these apparent stripes,
whether they run parallel with or at nearly right angles
to the direction of the hair, are due to almost hairless
spaces separating relatively long and thick ridges.

In addition to forming narrow ridges and furrows, the
hair may be so disposed in some foals as to produce wavy
bands across the croup, and faint lines at nearly right

angles to these across the hind quarters. The fairly wide
bands across the croup I have especially noticed in half-
bred bay foals. These bands, which are never due to
pigment, and are only seen in certain lights, fairly accu-
rately correspond in their position with the cross-bars of
the gridiron of the mountain zebra.

Evidently, in considering whether any given foal is
striped, the narrow tracks of hair, especially evident in the
vicinity of the flank feather, the wavy bands across the
croup, and the faint bands across the hind quarters, will

TELEGONY AND REVERSION. 157

have to be allowed for. Coming to Mulatto’s second foal,
it may first of all be mentioned that there were no stripes
on the face or across the shoulders, nor yet was there a
dorsal band; and though there were bars across the legs,
the bars were not so pronounced as in many purely-bred
foals—foals whose parents had never seen a zebra. More-
over, the leg bars were least distinct where they are
generally most marked in dun-coloured ponies, 7. e. in the
vicinity of the knee and hock. There was thus an all but
complete absence of the stripes that are ordinarily found
in the horse. In Lord Morton’s “ colts” besides a dorsal
band, there were “dark stripes across the forehead and
dark bars across the back part of the legs,”

and stripes
across the withers ; in the filly the stripes covered ‘‘ nearly
the whole of the neck and the back as far as the flanks.’’
There were, in fact, more stripes on the filly than on the
quagga hybrid. It seems to me that at least all the
stripes found in the filly over and above those in the
quagga hybrid must be credited to the black Arabian,
and not to the previous sire—the quagga. Why in
Mulatto’s second foal the stripes were not developed
along the spinal ridge and across the withers and hocks,
and were specially distinct across the croup and the front
of the arm, I am unable to say. That they failed to appear
in the usual position, and were more or less distinct in
unusual positions, may be considered by some as evidence
in favour of “infection.” The stripes on the neck and
legs need not be specially referred to, but the stripes
across the croup and hind quarters deserve very special
consideration.

In zebra-ass hybrids there are often numerous spots
over the croup and hind quarters. These spots were
present in a zebra-ass hybrid bred at Windsor during the
reign of George IV, and also in a hybrid between an
Asiatic ass and a zebra mare bred some years ago in
Paris. In Romulus there were, at birth, spots over the
croup, but in course of time the spots united to form
somewhat zigzag stripes. In one of the 1897 hybrids

158 TELEGONY AND REVERSION,

there were narrow bands over the croup from the first.
In Matopo the croup and hind quarters are almost entirely
occupied with the three flank stripes.

Evidently the bars across the croup in Mulatto’s second
foal have not been inherited directly from the first sire—
Matopo. Their presence might be accounted for by saying
they were latent in Mulatto, and that mating her with a
horse of a different strain led to their development. But
the offspring of the bay mare and of the dark-grey pony
by the same Arab horse, showed no markings across the
hind quarters. Is this because bays and dark greys are
less liable to produce striped offspring? If the croup
stripes in the second foal were not inherited from or induced
by the Arab horse, they, it may be argued, can only be
explained by saying that Mulatto has been in some way
influenced by her first mate—the zebra Matopo.

It thus appears that in Mulatto’s second foal, (1) the
stripes which most frequently occur in horses were absent;
(2) that there were certain stripes which are not uncommon
in horses ; and (3) that the most distinct markings present,
viz. the stripes across the croup, are extremely rare in
both foals and horses. While some of the stripes can
easily be accounted for by simple reversion, it is difficult
to account for others in this way.

In favour of the croup stripes having resulted from a
simple reversion due to the crossing of somewhat diverse
types, the experience of Darwin may be advanced. His
striped colt was of a mixed origin. The dam was a
descendant of a dark brown Flemish mare by a hght grey
Turcoman horse. The sire was Hercules, a thoroughbred
dark bay, whose sire (Kingston) and dam were both bays.
If the crossing of distinct types leads to reversion,
we can well understand Darwin’s striped colt being an
example of reversion; and in the same way the striping in
Mulatto’s second foal might also be due to mating more
or less distinct strains. Again, from the fact that the
second foal had stripes across the croup instead of rows of
spots as in Romulus, it might be argued that they could

‘TELEGONY AND REVERSION. 159

not be due to the influence of the previous sire. The dif-
ference in the marking of the croup between the first and
second foal might, however, be explained satisfactorily by
saying that in the one case the antagonism between the
units of germ-plasm had been greater than in the other,
with the result that the half-zebra Romulus reverted
further than the second foal, in which the zebra could only
be represented to the extent of about one part to thirty-
two of the horse.

From various experiments made with dogs, fowls, &.,
it is evident the amount of the reversion varies greatly,
e.g. while some of the cross-bred fowls already referred to
resembled not a little jungle fowls, others took after their
immediate maternal ancestor, the dark bantam. Again,
the offspring between a well-bred yellow collie and a
Dalmatian were not whole-coloured or wolf-like in appeav-
ance, nor yet were they spotted like the sire. They were,
in fact, extremely like foxhounds ; on a white ground colour
there are in each case several Jarge brown blotches. In
this case presumably the reversion has gone the length of
the less remote ancestors of the Dalmatian (said to be
pointers), but no further.

In favour of the croup stripes being due to “infection”
or telegony is the fact that, with the exception of the
New Forest pony’s foal, Benazrek’s offspring have hitherto
been quite devoid of stripes; and the New Forest pony,
having borne a mule foal to a jackass, may very well
have been “infected.” There is, however, a still stronger
argument, viz., that the percentage of chances is against
Mulatto producing a foal striped like Darwin’s colt. I
have been unable to find any records of foals characterised
by stripes over the croup or rump in addition to Darwin’s ;
and of the many experts who have examined Maulatto’s
second foal, not one had ever seen a colt so richly striped.
It is, of course, possible that thousands of foals have been
born with stripes over the hind quarters and loins—stripes
so indistinct that they escaped notice. If pronounced re-
version towards a striped ancestor is common, then there

160 TELEGONY AND REVERSION,

is nothing remarkable about the second foal; it is quite
unnecessary to search for an out-of-the-way explanation,
such as telegony supplies. If, on the other hand, croup
stripes are extremely rare, if they only occur once in say
every ten thousand foals, the chance of all the stripes on
the second foal being due to simple reversion is extremely
remote. Again, the Island of Rum ponies have been under
observation for many generations, and yet there 1s no
record of their foals ever having more than a dorsal band
and a cloudy patch over the withers.

Further, it may be pointed out that it is not a little
remarkable that both Lord Morton’s and Lord Mostyn’s
mares, after having borne quagga hybrids, produced some-
what zebra-like foals to horses. Had Mulatto not been
first mated with a zebra, she, like the grey Irish pony and
the well-bred bay mare, might have produced a foal devoid
of stripes, or with, at the most, a dorsal band and obscure
bars on the legs.

I may mention the mane, hoofs, and tail of Mulatto’s
second foal were, as far as I could judge, perfectly horse-
like ; that the eyes were hazel-coloured, as in Matopo and
in most of the West Highland ponies ; while the eyelashes
consisted partly of straight hairs, asin Mulatto, and partly
of the characteristic-curved hairs as in the zebra hybrids.

Although as the hair increased in length and the foal’s
coat was shed the markings erew fainter, the croup stripes
could still be detected at the end of December, when, un-
fortunately, Mulatto’s second foal succumbed to ailments
resulting from the presence of countless numbers of
the parasite Strongylus. Although evidence of reversion
could hardly be expected in the skeleton, I have examined
the condition of the ulna and of the second and fourth
digits. The ulna I found still complete, as complete as in
an eight months’ foetus; and with the exception of about
an inch (near but not quite at the lower end) completely
ossified, and affording a large articular surface for the
cuneiform or outer carpal bone. Further, the inner vestigial
digits, i.e. the vestiges of the second digits of both the

TELEGONY AND REVERSION. 16]

fore and hind limbs, are relatively large, although there is
no indication of either the middle or distal articulations.
In concluding this contribution to a difficult and complex
subject, I need neither point out that it would be pre-
mature to come to any conclusion as to whether there is
such a thing as “infection of the germ,” nor yet offer any
apology for recording the results thus far obtained.

APPENDIX.

APPENDIX.

TELEGONY.,
i:

Leavine out of consideration the question whether ac-
quired (¢. e, non-congenital) characters are transmitted,
there is no problem that claims wider attention at the
present time than what is now generally known as
Telegony.* Both naturalists and breeders are most anxious
to ascertain whether what has frequently been termed the
“infection of the germ” is possible—whether there is any
reason for the wide-spread belief that the first sire influences
the after progeny obtained by subsequent sires.

That the first impregnation has a lasting influence has
apparently long been credited by breeders, and since
Lord Morton (in 1820) communicated his famous letter to
the Royal Society, many naturalists have admitted the
possibility of the previous sire influencing the after progeny,
i. e. leading to an extraordinary kind of reversion or
“ throwing back.”

As Lord Morton’s “ experiment” is so often referred to,
it will be well to give in ful] the letter he addressed to the
President of the Royal Society. The letter is as follows:

“My Dear Sir,—I yesterday had an opportunity of
observing a singular fact in natural history, which you may
perhaps deem not unworthy of being communicated to the
Royal Society.

“Some years ago I was desirous of trying the experiment
of domesticating the quagga, and endeavoured to procure
some individuals of that species. I obtained a male; but
being disappointed of a female, I tried to breed from the
male quagga and a young chestuut mare of seven-eighths
Arabian blood, and which had never been bred from. The

* From 7A, at a distance, and ydvoe, offspring.

166 APPENDIX.

result was the production of a female hybrid, now five
years old, and bearing, both in her form and in her colour,
very decided indications of her mixed origin. I subse-
quently parted with the seven-eighths Arabian mare to
Sir Gore Ouseley, who has bred from her by a very fine
black Arabian horse. I yesterday morning examined the
produce—namely, a two-year-old filly and a year-old colt.
They have the character of the Arabian breed as decidedly
as can be expected where fifteen-sixteenths of the blood
are Arabian, and they are fine specimens of that breed;
but, both in their colour and in the hair of their manes,
they have a striking resemblance to the quagga. Their
colour is bay, marked more or less like the quagga ina
darker tint. Bothare distinguished by the dark line along
the ridge of the back, the dark stripes across the fore-hand,
and the dark bars across the back part of the legs. The
stripes of the colt are confined to the withers, and to the
part of the neck next to them. Those on the filly cover
nearly the whole of the neck, and the back as far as the
flanks. The colour of her coat on the neck adjoining to
the mane is pale, and approaching to dun, rendering the
stripes there more conspicuous than those on the colt.
The same pale tint appears in a less degree on the rump ;
and in this circumstance of the dun tint also she resembles
the quagga. The colt and filly were taken up from grass
for my inspection, and, owing to the present state of their
coats, I could not ascertain whether they bear any indica-
tions of the spots on the rump, the dark pasterns, or the
narrow stripes on the forehead, with which the quagga is
marked. They have no appearance of the dark line along
the belly, or of the white tufts on the sides of the mane.
Both their manes are black; that of the filly is short, stiff,
and stands upright, and Sir Gore Ouseley’s stud-groom
alleged that it never was otherwise. That of the colt is
long, but so stiff as to arch upwards and to hang clear of
the sides of the neck, in which circumstance it resembles
that of the hybrid. This is the more remarkable, as the
manes of the Arabian breed hang lank, and closer to the

APPENDIX. 167

neck than those of most others. The bars across the legs,
both of the hybrid and of the colt and filly, are more
strongly defined and darker than those on the legs of the
quagea, which are very slightly marked ; and though the
hybrid has several quagga marks, which the colt and filly
have not, yet the most striking, namely, the stripes on the
fore-hand, are fewer and less apparent than those on the
colt and filly. These circumstances may appear singular ;
but I think you will agree with me that they are trifles com-
pared with the extraordinary fact of so many striking
features, which do not belong to the dam, being in two
successive instances communicated through her to the
progeny, not only of another sire, who also has them
not, but of a sire belonging probably to another species,
for such we have very strong reason for supposing the
quagea to be.
“T am, my dear Sir,
« Your faithful humble servant,
“ Morton.
“Dr. W. H. Wollaston.

“P.S.—I have requested Sir Gore Ouseley to send me
some specimens of hair from the manes of the sire, dam,
colt, and filly; and I shall write to Scotland for specimens
trom those of the quagga and of the hybrid.

“JT am not apt to build hypotheses in a hurry, and have
no predilection either for or against the old doctrine of
impressions produced by the imagination; but I can hardly
suppose that the imagination could pass by the white tufts
on the quagga’s mane and attach itself to the coarseness of
its hair.

“ Wimpole Street, August 12th, 1820.”

Note by Dr. Wollaston.

‘By the kindness of Sir Gore Ouseley, I had an oppor-
tunity of seeing the mare, the Arabian horse, the filly, and

168 APPENDIX.

the colt, and of witnessing how correctly they agreed with
the description given of them by Lord Morton.” *

In considering this case, the question at once arises,
Were the quagga-like markings of the colt and filly due to
the mare having been infected by the qnagga, or were
they due to reversion—to the reappearance of certain
ancestral characters ? To this question « final answer has
not yet been given.

Quagga-like bands are often seen on the shoulders
and legs of horses. I have before me a photograph of a
Norwegian pony taken some days ago, which shows four
distinct bands on the shoulder, in addition to the dorsal
stripe, and distinct bands on the neck and trunk.

Darwin, after devoting much attention to the occurrence
of bands on horses, states that ‘in all parts of the world
stripes of a dark colour frequently appear along the spine,
across the legs, and on the shoulders, where they are
oceasionally double or treble, and even sometimes on the
face and body, of all breeds of horses, and of all colours.” F

Nevertheless, after discussing at some length Lord
Morton’s case, he concludes by saying, ‘‘there can be no
doubt that the quagga affected the character of the offspring
subsequently got by the black Arabian horse.” {

Since Lord Morton’s letter was published, numerous
cases of supposed “infection of the germ” have been put
on record, and quite recently a keen discussion on telegony
has been carried on in the pages of the Contemporary
Review between Weismann, Herbert Spencer, and Romanes.

Spencer firmly believes in telegony, and sets forth at
considerable length how the germ-cells are infected. He
apparently believes that as the embryo develops, germ-
plasm passes from it into, and becomes a permanent part
of, the body of the parent, and that later some of this germ-
plasm everywhere diffused reaches and is incorporated 1n

* ©Philosophical Transactions,’ 1820, p. 21.
+ ‘Animals and Plants,’ vol. i, p. 15.
£ Ibid., vol. i, p. 435.

APPENDIX. 169
the germ-cells—i.e. he believes in what might be called
the indirect “infection of the germ.”

Romanes, in giving the main results of a lengthened
inquiry on this subject, writes as follows : *—‘ The inves-
tigations have been pursued on three different lines: (1)
I raised discussions on the subject in the principal breeders’
and fanciers’ journals of this country and also of America.
(2) I entered into private correspondence with contributors
of the largest experience, and also with professional and
amateur breeders, fanciers, &c., who addressed me directly
on the subject. (3) I started experiments with the varieties
which these inquiries indicated as most likely to yield
positive results. At present nothing need be said with
regard to these experiments, because they are not suffi-
ciently matured; but it is desirable to state the general
upshot of the correspondence.

“The principal result is to show that the phenomenon
is of much less frequent occurrence than is generally
supposed. Indeed, it is so rare that I doubt whether it
takes place in more than one or two per cent. of cases. I
must add, however, that nearly all my professional corre-
spondents would deem this an absurdly low estimate. It has
hitherto puzzled me why the phenomenon in question, since
it does certainly occur in some cases, should occur so rarely.
But I think that Mr. Spencer’s suggestion on this point is
avaluable one. This suggestion is that when the first sire
is of a relatively stable and also of a markedly different
ancestral stock from the dam, there will be most likelihood
of his impressing his ancestral characters on the progeny
of the second sire.”

While Romanes evidently believes in the possibility of
telegony, he is far from accepting Spencer’s explanation
of the phenomenon. He adopts the simpler explanation
that the unused germ-plasm from the first sire directly
infects—gains access to—the unripe ova. In holding this
view, Romanes seems to be in agreement with Darwin, who
apparently believed that the male element acts directly on

* ©An Examination of Weismannism,’ 1893, Appendix II.

170 APPENDIX.

the reproductive organs of the female, and not through the
intervention of the crossed embryo.

Another believer in telegony who may be mentioned is
Agassiz. As the result of various experiments, he satisfied
himself “that the act of fecundation is not an act which is
limited in its effect, but that it is an act which affects the
whole system, the sexual system especially ; and in the
sexual system the ovary to be impregnated hereafter is so
modified by the first act, that later impregnations do not
efface that first impression.”

But while Darwin, Spencer, Agassiz, and Romanes believe
more or less firmly in telegony, there are many who are
either doubters or unbelievers. The most prominent of
these is Weismann, who inclines to the view that there is
no such thing as an “infection of the germ.” In a
recent number of the Contemporary Review* he writes as
follows:

“JT must say that to this day, and in spite of the addi-
tional cases brought forward by Spencer and Romanes, I
do not consider that telezony has been proved.

*“Tdo not dispute the possibility of telegony ; I grant
that the wide general acceptance of the belief in the past
has so impressed me that I have always said that possibly
it might be justifiable and founded on fact. I should
accept a case hke that of Lord Morton’s mare as satis-
factory evidence if it were quite certainly beyond doubt,
But that is by no means the case, as Settegast has abun-
dantly proved.”

Weismann does not doubt that after the mare had borne
ahybrid toa quagga she subsequently had colts by a horse,
and that these were marked with stripes on the neck,
withers, and legs, but he contends that there were no
other characteristics of the quagega discernible in the colts.
‘The stripes do not in themselves, Settegast thinks, amount
to proot, ‘for every experienced horse-breeder knows ”
that ‘cases are not very rare in which colts are born with
stripes that recall those of the quagga or zebra. They

* Vol. Ixiv.

APPENDIX. 171

regularly disappear as the colts increase in age.” Weis-
mann refers to other experiments, and adds,“ the attempt
must be made to determine the truth by new experi-
ments.”

* But as hitherto,’ Weismann adds, “ there have been
no positive results from the observations that have been
made ; and as the most competent judges, namely, breeders
who have a scientific knowledge, such as Settegast and
Nathusius, and the late head of the Prussian Agricultural
Station at Halle, Professor Kiihn, spite of their extensive
experience in breeding and crossing, have never known a
case of telegony, and therefore have great doubts as to its
reality, it seems to me that, ‘ according to scientific principles,
only the confirmation of the tradition by methodical investi-
yation, in this case by experiment, could raise telegony to the

rank of a fact.”

~ In concluding his observations on telegony,* Weismann
says :—‘ Experienced breeders, like Settegast and Kiihn,
of Halle, do not believe in it, for though they have crossed
various domestic animals they have never observed an
instance of it... . If the ‘infection’ were proved beyond
a doubt, a supplementary fertilisation of an egg-cell in this
inanner must be considered possible; we certainly might
then reasonably ask why mares, cows, or sheep should not
occasionally become pregnant without being served a
second time. But this has never yet been known to occur,
and I incline to Settegast’s view, that thereis no such thing
as an ‘infection’ of this kind, and that all the instances
which have been recorded and discussed critically by him
are based upon a misconception.”

Thus the case stands at the present day. At the one
extreme we have Weismann and certain experienced Ger-
man breeders; at the other many English breeders so
persuaded that telegony is of frequent occurrence that they
make a point of always mating their mares, &c., first with
a male having a good pedigree, so that their subsequent

* ¢Germ-plasm,’ p. 385.

172 APPENDIX.

progeny may be henefited by his influence even though
inferior sires are subsequently resorted to.

Evidently this is a question of as much practical im-
portance as it is of profound scientific interest, and ib 1s
a question which both men of science and breeders are
alike agreed should, if possible, be settled without further
delay.

By way of making an attempt in this direction I am
anxious to organise an extensive series of experiments, and
my chief object in writing this paper is to enlist the terest
and co-operation of breeders and others in a position to
render assistance.

I propose to repeat as exactly as possible Lord Morton’s
experiment, using, however, a zebra in place of the now
extinct quagga. I have already obtained a number of
mares, but as, according to Romanes, telegony may only
occur in a very small percentage of cases, I shall be glad to
hear from any one who is willing to place a suitable mare
at my disposal. But in addition to crossing the horse and
zebra, it is most desirable that experiments be made with
cattle, sheep, pigs, dogs, &c., of various breeds. May I
venture to appeal to those sufficiently interested in the
question who happen to be in a position that admits of
their taking part in the work to communicate with me, so
that the necessary arrangements for further experiment
may be made. In the next number of this Journal I shall
give a list of the experiments which I think might be
started during the present season.

Il.

In the paper on Telegony published in the April
number of The Veterinarian, after quoting in full the now
famous letter of Lord Morton, I especially referred to the
views of Darwin, Herbert Spencer, Agassiz, Romanes,
and Weismann. Since this paper appeared I have had the
opportunity of reading the recently published work on

APPENDIX. 173:

horses, asses, &c., by Tegetmeier and Sutherland.* As
the one writer has long taken a keen interest in almost all
branches of natural history, and more especially in the
crossing of various kinds of animals, while the other has
been long successfully engaged in breeding mules, it will
be well to indicate their views on the subject under con-
sideration. They better than any others may, I think, be
held as representing the views generally prevailing
amongst not only breeders, but all who take an interest in
our domestic and semi-domestic animals.

Some breeders of mules accept the infection of the germ
theory ; others, who have had considerable experience in
the United States, affirm they have never seen any evidence:
of the influence of the first sire on the subsequent progeny
to other sires.

Believers in telegony frequently refer to the progeny
of an African ass (Hquus asinus) obtained by the Zoo-
logical Society of London in 1881. This ass produced her
first foal in June, 1883, the other parent being an Asiatic
ass (H. hemionus). The hybrid foal closely resembled the
male parent, which was reddish in colour, the female being
of the usual grey. In 1889 and again in 1891 this female
African ass produced a foal to an African male ass. Both
foals presented the usual characters of the common or
African ass. But in 1892 + a third foal was born to the
same African male ass; and this foal was of a reddish
fawn-colour, somewhat shaggy in coat, and provided with
a large star on the forehead and a white blaze down the
face, while the ears were relatively short and the shoulder
and leg stripes indistinct.

This departure from the normal type might either be
due (1) to simple reversion, (2) to what would now-a-days
be designated discontinuous variation, or (3) to telegony—
in this case to the influence of the Asiatic first sire.

In discussing this case the writers say: “ The influence

* © Horses, Asses, Zebras, and Mules,’ Horace Cox, Field Office, 1895.

+ Recently (1898) this ass has produced a second reddish-coloured foal.
like her first mate the Asiatic ass.

174. APPENDIX.

of the first sire on all subsequent offspring is a subject of
very considerable importance, that has not received the
scientific investigation that it merits. It is generally
accepted by breeders of dogs, and in the case of valuable
animals the effect of a mésalliance is carefully guarded
against. It is one that is recognised by physiologists as
affecting the human species,* and the example of the
striped foals that were always bred by a mare whose first
foal was a hybrid of zebra parentage is well known.”

“Whether this young ass bred in the Gardens is merely
an accidental variation, or whether it owes its peculiarities
to the influence of the Hemippe [Asiatic first sire] is a
point I will not endeavour to decide.” T

In the chapters on mules and mule-breeding the influ-
ence of the first sire is again referred to. In support of
the statement that male and female mules and hinnies are,
as far as is known, “ absolutely sterile,’ the authors quote
from Captain Hayes as follows:

“ Neither the mule (the produce of the jackass and
mare) nor the hinny or jennet (the cross between the
horse and the she-ass) is fertile, either among themselves
or with other members of the horse family. Those animals
which have been mistaken by superficial observers as fertile
mules have been, I venture to say, in most cases the off-
spring of mares that have previously bred to donkeys, and
have endowed their young with some of the characteristics
of their former asinine lovers. Both the mule and the
jennet respectively ‘take after’ their dam in size, and
their sire in appearance and disposition.”

That the authors agree with Captain Hayes may be
gathered from what they say as to the ‘“ mule” which
produced foals to both the horse and the ass in the Accli-
matisation Gardens in Paris. After pointing out that “it
is doubtful whether the animal is a mule,” they add, “ It
is not at all improbable that her female parent had bred a

* T have never heard of a well-authenticated case of telegony in the

human species.—J. C. E.
7 Ibid., pp. 15 and 16.

APPENDIX. 175

mule in the first instance, and, as in the well-known cases
of mares which have been mated with quagegas and zebras,
her subsequent progeny, when mated with a horse, shows
some trace of the first union. The late M. Ayrault, and
most persons who are really cognizant of the matter,
regard this animal not as a mule but as an ordinary mare.
. . . It would appear most probable that this is not a case
of a fertile mule breeding ; but that the animal is really
an ordinary mare, whose female parent was influenced by
a first alliance, as is so often the case in dogs and other
animals.’’*

From these quotations it “may be assumed (1) that
Tegetmeier and Sutherland believe in telegony in “the
case of dogs and other animals,”’ and that it most probably
occurs also in horses, and (2) that Captain Hayes (who
probably expresses the views of the majority of veterina-
rians) takes for granted that telegony occurs in horses as
well as in other animals.

The views held by biologists, breeders, and others in-
terested in the question of telegony having been shortly
stated, I shall now indicate some experiments that might
at the outset be started. Granting that infection of the
germ is possible, various questions at once arise. Is it, as
believed by Romanes, extremely rare, or is it, as asserted by
many breeders, of common occurrence? It is conceivable
that it may be of common occurrence, but owing to in-
breeding and other causes the results in the majority of
cases may be completely or all but completely obscured.

In planning experiments it will, I think, be well to take
for granted that if telegony occurs at all it occurs fre-
quently, and that in order to demonstrate the influence of
the first sire it is only necessary to select suitable subjects.

Judging by the cases already reported which seem to
support the belief in telegony, it will be desirable to, in
the first instance, operate with either different species or
well-marked varieties of the same species, and then mate
the females which have bred to the new species or distinct

* Tbid., pp. 81 and 82.

176 APPENDIX.

varieties with males of their own particular breed. The
following are the crosses that I think might well be tried.

1. A male zebra and various breeds of mares,—each
fertile mare to be afterwards mated with an Arab horse, or
a horse of its own particular breed.

2. An Arab or other distinct breed of horses and a
zebra mare,—the zebra mare, if fertile, to be afterwards
mated with a male zebra.

3. A male zebra and a jennet, the jennet to be afterwards
bred to a jackass.

4, A jackass and a mare, the mare to be afterwards
mated with a horse.

5. A zebu bull and a Kerry and au Ayrshire cow, the
cows to be afterwards bred to their respective bulls.

6. A Chillingham bull and Galloway, Angus, Norfolk,
and Devon cows, each cow to be afterwards mated with a
bull of its own breed.

7. A Galloway bull and a shorthorn cow, the cow to be
afterwards mated with a shorthorn bull.

8. An Aberdeen Angus bull and a shorthorn cow, the
cow to be afterwards mated with a shorthorn bull.

9, A red shorthorn and a Dutch cow, the cow to be
afterwards mated with a Dutch bull.

10. A Leicester tup and a black-faced ewe, the ewe to
be afterwards mated with a black-faced tup.

11. An Iceland tup and a Shropshire ewe, the ewe to be
afterwards mated with a Shropshire tup.

12. A Southdown tup and a merino ewe, the ewe to be
afterwards mated with a merino tup.

15. A goat and a ewe, the ewe, if fertile, to be after-
wards mated with a tup of her own breed.

14. A Berkshire boar and a Tamworth sow, the sow to
be afterwards mated with a Tamworth boar.

15. An Irish boar and a Tamworth sow, the sow to be
afterwards mated with a Tamworth boar.

The above are merely offered as suggestions ; many other
crosses might be equally or even more successful in

APPENDIX. 177

throwing light on the question at issue. I shall be glad to
hear from anyone willing to undertake any of the above
or similar experiments. I have not made any suggestions
as to experiments with dogs, rabbits, ducks, fowls, &c.
This is not because I think valuable results might not be
obtained, but rather because breeders and fanciers willing
to take part in the investigation, can settle best for them-
selves, on what particular lines they might most successfully
work with the domestic animals not specially referred to.
The first three crosses suggested I am making arrange-
ments to carry out with as little delay as possible.

PRINTED BY ADLARD AND SON,
BARTHOLOMEW CLOSE, E.C., AND 20 HANOVER SQUARE, W.

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