Aucust 3, 1899] 
NATURE 
331 
tion” is commonly supposed to lead to ‘‘ throwing back” to a 
previous sire many instances could be given, but the following 
from an article on telegony by De Varigny will suffice. De 
Varigny states that an ordinary cat which had kittens to a tail- 
less Manx cat subsequently produced several tailless kittens to 
a normal cat of her own breed (Journal des Débats, September 
9, 1897). — je 
An extended series of experiments with various kinds of 
animals has led me to the conclusion that if there is such a 
thing as telegony it is more likely to result in the subsequent 
offspring ‘throwing back” to an ancestor of the ‘‘infected” 
dam than to a previous mate. This view of telegony (which 
has not been insisted on hitherto) will be made at once evident 
by an example. A sable collie crossed with a Dalmatian pro- 
duced three pups which in their coloration are extremely like 
young foxhounds; instead of numerous small spots each has a 
few large blotches. According to the common view of telegony 
this collie, if infected, should next produce with a dog of her | 
own breed one or more Dalmatian-like pups. If, however, the 
offspring of a collie and a Dalmatian are like foxhounds the | 
subsequent offspring to a collie of the same colour and strain 
could hardly be expected to present Dalmatian characters, 7.c. 
show numerous small spots. But if ‘‘infection” as a rule 
results in the subsequent offspring ‘‘ throwing back” either to 
the ancestors of the sire or the dam, it will be extremely difficult, 
if not in many cases impossible, to distinguish telegony from 
simple reversion.? 
But though “infection,” if it does take place, is likely, as 
a rule, to lead the subsequent offspring to resemble the an- 
cestors of the dam, it may in certain cases possibly lead to their 
“throwing back” toa previous sire. This result might follow 
if the previous sire happened to be highly prepotent. For 
example, Highland heifers often produce to a Galloway bull 
hornless black offspring indistinguishable from pure Galloways. 
If infected by the Galloway bull, these heifers might afterwards 
produce Galloway-like calves when mated with long-horned 
bright coloured bulls of their own breed. 
It is now commonly believed that if there is such a thing as 
telegony it results from the unused germ cells of the first (or 
previous) sire infecting—blending with—the unripe germ cells 
in the ovaries of the dam. Were this possible, the- subsequent 
progeny would in all probability in a mild way resemble the 
previous sire, but if this is impossible then infection—due 
perhaps to some obscure change in the constitution or reproduc- 
tive system of the dam—is more likely to lead to more or less 
marked reversion to the ancestors of the dam. All my observ- 
ations point to its being impossible in the Equide for the unused | 
male germ cells of the first sire to infect the unripe ova. The 
spermatozoa lodged in the upper dilated part of the oviduct of 
the mare are dead, and in process of disintegrating, eight days 
after insemination ; they probably lose their fertilising power 
in four or five days. There is no reason for supposing that in 
the Equidee they survive longer in or around the ovary. Further, 
though at the time of fertilisation there may be several large 
Graafian follicles in each ovary containing maturing ova, all 
these follicles disappear long before the period of gestation is 
completed. The subsequent foals are developed from successive 
new crops of ova into the composition of which it is incon- 
ceivable any of the spermatozoa of the first sire could by any 
chance enter. A study of the ovaries hence tends to confirm 
the view that ‘‘ infection” (if there is such a thing) is as likely 
to cause reversion to a former ancestor of the dam as a ‘‘ throw- 
ing back ”’ to a previous sire. 
Having made these general observations, it will be well next 
to consider critically the case of ‘‘ infection’? communicated in | 
y 
the letter to the President of the Royal Society in 1820? by the 
Earl of Morton, Though many other instances of supposed 
“infection” have been recorded, Lord Morton’s mare may be 
said to still hold the field—the theory of telegony still mainly | 
rests on the assumption that this historic mare was ‘‘ infected” 
by a quagga some years before she passed into the hands of Sir 
Gore Ouseley and produced three ‘‘colts” to a black Arabian 
horse. One might even go further and without much ex- 
aggeration assert that the telegony hypothesis at the present 
1 That reversion ever occurs has been questioned by Bateson (‘‘ Materials 
for the Study of Variation”) and others, but I have already (NaTuRE, 
February 9, 1899) proved beyond doubt that reversion can be easily in- 
duced by intercrossing distinct types, and I have recently heard of several 
instances of spontaneous reversion—reversion not induced by intercrossing. 
2 Phil. Trans., 1821. 
NO. 1553, VOL. 60] 
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moment mainly rests on an allegation by Sir Gore Ouseley’s 
stud groom. 
It has been generally assumed that Lord Morton’s mare (a 
nearly purely bred chestnut Arab) was ‘‘infected” for two 
reasons (1) because the subsequent offspring were of a yellowish- 
brown colour and more or less striped, and (2) because, ac- 
cording to Sir Gore Ouseley’s stud groom, the mane of one of 
the striped foals had always been upright, while in another it 
arched to one side clear of the neck. The presence of stripes 
in the subsequent offspring has never been questioned, nor yet 
is there any doubt that when Lord Morton in 1820 inspected the 
“colts” the mane in the filly was upright as in the quagga, 
while that of the colt resembled the mane of Lord Morton’s 
quagga hybrid. There is, however, an absence of trustworthy 
evidence that the filly’s mane had a/ways been upright as 
alleged to Lord Morton by Sir Gore Ouseley’s stud groom. 
Were the evidence in support of this allegation satisfactory, 
there would I think be no escape from the conclusion that Lord 
Morton’s mare was ‘‘infected” by the quagga. Hitherto the 
presence of stripes on the ‘‘colts’’ has generally been looked 
upon as affording strong evidence of ‘‘ infection.” Believers in 
telegony admit that stripes are not uncommon in Norwegian 
and certain other breeds of horses, but, with Mr. Darwin, 
they have taken for granted that they never or very rarely occur 
in Arabs. 
I find, however, that though in Arabia dun-coloured horses 
are disliked and never used for breeding, stripes even in the 
most renowned strains are not so uncommon as is generally 
supposed. I have now a purely bred Arab filly of about the 
same colour as Lord Morton’s filly, but, unlike the filly we have 
heard so much of, both the fore and hind legs are marked with 
distinct dark bars, and there are faint indications of stripes 
across the withers and a distinct dorsal band. The history of 
this filly (bred by Mr. Wilfred Scawen Blunt at Crabbet Park, 
Sussex, and very kindly presented to me) is ,well known for 
many generations ; none of her ancestors could possibly have 
been ‘‘infected” by a zebra. The dun colour and stripes are 
doubtless the result of simple spontaneous reversion, for, unlike 
Lord Morton’s mare, there is no history of a cross in her 
pedigree. This filly proves that even in high-caste Arabs of 
the best desert blood a dun colour and stripes may unexpectedly 
appear. 
As to the occurrence of stripes in other breeds I could give, 
were it necessary, many instances. A year ago I had in my 
possession a light bay (or yellow dun) pony, which showed 
nearly as many stripes on the trunk as the Gore-Ouseley filly, 
and in addition had several interrupted narrow stripes on the 
forehead.1_ Moreover, the stripes on the Gore-Ouseley ‘‘ colts,” 
while agreeing with stripes occasionally seen in horses, differ in 
their arrangement from the stripes in the quagga. The stripes 
themselves are evidence of reversion, but nothing more; and 
seeing that pure bred horses sometimes show quite as many 
stripes, we are not justified in assuming that but for the dam of 
the ‘‘colts” having been first mated with a quagga the stripes 
would not have appeared. 
Hence unless it is proved that the mane in the filly and colt 
were naturally erect, or nearly erect, the case for the ‘‘ infec- 
tion” of Lord Morton’s mare will be lost. It may be well to 
quote the passage from Lord Morton’s letter referring to the 
mane. Itis as follows :—‘‘ That of the filly is short, stiff, and 
upright, and Sir Gore Ouseley’s stud groom alleged it never was 
otherwise. That of the colt is long, but so stiff as to arch up- 
wards and to hang clear 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 
neck than that of most others ” (PA2/. Trans. 1821). 
I am not prepared to accept the allegation as to the manes for 
the following reasons :— 
(1) I have had twelve zebra hybrids under observation, and 
in each case the mane, though erect to start with, always after a 
time arched over to one or both sides. The stud groom’s 
statement, it seems to me, proves too much. If in the quagga 
hybrid and in all my horse hybrids the mane, sooner or later, 
falls to one side it is a little remarkable that in the pure bred 
two-year-old filly it had been always upright. 
I may here mention that the hair of the mane of zebra hybrids 
is shed annually ; it is for this reason that the mane in hybrids is 
never long enough to hang close to the neck. 
(2) The mane in the drawing of the filly by Agassé is no 
1 See Fig. 36, ‘‘ The Penycuik Experiments,” A. and C. Black, 1899. 
