insisted, especially in the case of the Mauchamp race, that they had
each descended from, or been crossed with, some unknown aborig-
The Paraguay cattle are a hornless race which is composed of
the descendants of a hornless bull which was born in Paraguay in
A recent interesting case wholly parallel with those just recorded,
is that of the Polled Herefords originating in 1889 in Kansas, U.
S. A_(see Guthrie, W. W., "History of Polled Herefords," in Proc.
Am. Breeders' Assoc., Vol. II, pp. 93-95, 1906).
"In the fall of 1889, W. W. Guthrie, Sr., of Atchison, Kansas,
now deceased, discovered among the calves that had been weaned
A recent ex- at n ' s rancn m Chase County, Kansas, one with Here-
ample of race ford markings which was perfectly polled. In his
origin from a herd were purebred Shorthorn as well as purebred
ttle ' Hereford cows. Two purebred Hereford bulls were
at the head of the herd. This calf was the product of a three-
quarter Hereford and one-quarter Shorthorn cow by one of the
two purebred Hereford bulls, Grateful 3d, No. 8,001, and Treasurer,
No. 10,585. Discovery, as the calf -was subsequently named, was a
well-formed animal, with a good loin, and well-developed hind-
quarters, and had the Hereford colour and markings, with body
more on the type of the Shorthorn. At three years of age he
weighed, without special feeding, 1,986 Ibs.
"It then occurred to Mr. Guthrie that by using this animal he
might in time establish a herd of polled Herefords, and that the
experiment was at least worth trying. Shortly afterwards, he
happened to meet on the train Chancellor Snow, of the Kansas
State University, on his way to lecture before the Atchison High
School on evolution, and during their several hours conversation
discussed with him the proposition of animal architecture. The
Chancellor agreed that the proposition of establishing a polled
Hereford herd was one worth considering, and Mr. Guthrie deter-
mined to carry out his ideas along this line.
OTHER THEORIES OF SPECIES-FORMING. 359
"When Discovery matured it was found that his calves from
horned cows were all hornless. In 1893, a two-year-old bull and
six heifers were selected and brought to Atchison County, where
the experiment was carried on under the personal supervision of
Mr. Guthrie and with very encouraging results.
"On October 31, 1898, Mr. Guthrie purchased at the Kansas City
Scott & Whitmann sale four purebred Hereford heifers. The calves
from these horned heifers by a descendant of Discovery were found
to be in every instance polled, only two showing scurs, scarcely
noticeable, and loose in the skin. A number of purebred Hereford
heifers were later obtained from the Funkhouser herd, and still
later others from the Armour herd, and equally good results were
"Eight head of polled Herefords were exhibited by Mr. Guthrie
at the Omaha Exposition, and, while these animals did not present
the finished appearance of modern show cattle, not having been
forced from date of birth, they attracted such attention that articles
on the herd were published in the newspapers and periodicals
throughout this country, and even in such far-away lands as Aus-
tralia and New Zealand.
"The desirability of Herefords without horns, the one objection
which Hereford breeders had been willing to admit, becoming appa-
rent, other Hereford breeders began to take notice of an occasional
polled calf, freaks of nature as they were considered, appearing
in their herds, and soon a brisk demand for polled bulls developed,
animals being shipped as far north as South Dakota, and Wiscon-
sin, and as far south as Texas. Breeders in many instances have
reported that in their horned herds, after several years' breeding,
not a single calf had come with horns, and only occasionally would
slight scurs, loose in the skin, appear." . . .
"In December, 1904, four head of polled Herefords from West
Virginia were exhibited at the International Live Stock Show at
Chicago in connection with horned Herefords, and during the past
season a larger number from the same State were exhibited through-
out the eastern circuit of fairs. At the American Royal Cattle
Show at Kansas City, last October, seven head from the original
herd were exhibited. As a result of these exhibits, many horned
Hereford breeders are now turning their attention to the subject of
breeding Herefords without horns, and so great has become the
demand for animals with which to start polled herds that at the
last meet of the National Polled Hereford Breeders' Association it
was found that the members were unable to supply enough young
bulls to meet the demand.
"Quite a number of purebred Hereford calves, termed 'freaks'
or 'sports,' have been dropped in this country, and some have been
kept. The President of the National Polled Hereford Breeders'
Association has a perfectly polled cow, the produce of one of his
purebred horned Hereford cows by a purebred horned Hereford
bull, and has lately purchased a purebred polled Hereford bull.
The original herd now contains two polled males and a number of
polled females, descended direct from purebred Herefords. The
above animals are registered in the American Hereford Record.
"During a trip through England several years ago, Mr. Guthrie
made inquiry among Hereford breeders and found that, while an
occasional polled animal had been calved, they were considered as
freaks of nature by the owners and butchered."
8 Bateson, Wm., "Materials for the Study of Variation," 1894.
* Kolliker, A. von, "Uber die Darwin'sche Schopfungstheorie,"
Zeitsch. f. wiss. Zool, Vol. XIV, pp. 174-186, 1864.
1 Dall, W. H., 1877.
* Galton, Francis, "Natural Inheritance," p. 32, 1889.
* Galton, Francis, loc. cit. p. 27, "The distinction between primary
Gallon's dis- arj d subordinate positions of stability will be made
cussion of spe- clearer by the help of Fig. i, which is drawn from a
oifio stability. model I made. The model has more sides, but Fig.
I suffices for illustration. It is a polygonal slab that can be made to
stand on any one of its edges when set upon a level table, and is
intended to illustrate the meaning of primary and subordinate
stability in organic structures, although the conditions of these must
be far more complex than anything we have wits to imagine. The
model and the organic structure have the cardinal fact in com-
mon, that if either is disturbed without transgressing the range
of its stability, it will tend to reestablish itself, but if the range is
overpassed it will topple over into a new position; also that both
of them are more likely to topple over towards the position of
primary stability, than away from it.
The ultimate point to be illustrated is this. Though a long
established race habitually breeds true to its kind, subject to small
OTHER THEORIES OF SPECIES-FORMING. 361
unstable deviations, yet every now and then the offspring of these
deviations do not tend to revert, but possess some small stability
of their own. They, therefore, have the character of sub-types,
always, however, with a reserved tendency, under strained condi-
tions, to revert to the earlier type. The model further illustrates
the fact that sometimes a sport may occur of such marked pecu-
liarity and stability as to rank as a new type, capable of becoming
the origin of a new race with very little assistance on the part of
natural selection. Also, that a new type may be reached without
any large single stride, but through a fortunate and rapid succession
of many small ones.
"The model is a polygonal slab, the polygon being one that
might have been described within an oval, and it is so shaped as
to stand on any one of its edges. When the slab rests, as in Fig i,
on the edge A B, corresponding to the shorter diameter of the oval,
it stands in its most stable position, and in one from which it is-
equally difficult to dislodge it by a tilt either forwards or back-
wards. So long as it is merely tilted it will fall back on being
left alone, and its position when merely tilted corresponds to a simple
deviation. But when it is pushed with sufficient force, it will tumble
on to the next edge, B C, into a new position of stability. It will
rest there, but less securely than in its first position ; moreover, its
range of stability will no longer be disposed symmetrically. A com-
paratively slight push from the front will suffice to make it tumble
back, a comparatively heavy push from behind is needed to make it
tumble forward. If it be tumbled over into a third position (not
shown in the figure), the process just described may recur with
exaggerated effect, and similarly for many subsequent ones. If,
however, the slab is at length brought to rest on the edge C D, most
nearly corresponding to its longest diameter, the next onward push,
which may be very slight, will suffice to topple it over into an
entirely new system of stability; in other words, a 'sport' comes
suddenly into existence. Or the figure might have been drawn with
its longest diameter passing into a projecting spur, so that a push
of extreme strength would be required to topple it entirely over.
"If the first position, A B, is taken to represent a type, the other
portions will represent sub-types. All the stable positions on the
same side of the longer diameter are subordinate to the first position.
On whichever of them the polygon may stand, its principal tendency
on being seriously disturbed will be to fall back towards the first
position ; yet each position is stable within certain limits.
"Consequently, the model illustrates how the following condi-
tions may co-exist: (i) variability within narrow limits without
prejudice to the purity of the breed; (2) partly stable sub-types;
362 DARWINISM TO-DAY.
(3) tendency, when much disturbed, to revert from a sub-type to
an earlier form; (4) occasional sports which may give rise to new
10 Emery, C, "Gedanken zur Descendenz- und Vererbungstheorie,"
Biolog. Centralbl, Vol. XIII, pp. 397-420, 1893.
11 Korschinsky, S., "Heterogenesis und Evolution," Naturw.
Wochenscrift, Vol. XIV, pp. 273-278, 1899; also "Heterogenesis u.
Evolution," Flora, oder Allg. Bot. Zeit., Erganzungsbd. 89, pp. 240-
13 De Vries, H., "Die Mutationstheorie," Vol. I, 1901, Vol. II,
Beferences to " ^ e Vries, H., "Species and Varieties, Their
discussions by Origin by Mutation" (ed. by MacDougal), 1905.
de Vries of spe- 14 De Vries, H., "Die Mutationstheorie," Vol. I,
oies-forming. p I5Oj Ipol
1S De Vries, H., "Die Mutationstheorie, Vol. I, p. 362, 1901.
18 De Vries, H.,." Species and Varieties," p. 6.
1T De Vries, H., "Species and Varieties," pp. 8-9.
18 De Vries, H., "Species and Varieties," p. 10.
18 De Vries, H., "Species and Varieties," p. 13.
20 For an excellent exposition and discussion of the de Vries muta-
tion theory and mutations, see Lotsy, J. P., "Vorlesungen iiber De-
scendenztheorien," Vol. I, chaps, xiv and xv, 1906.
21 Morgan, T. H.. "Evolution and Adaptation," pp. 294-295, 1903.
21 As evidence of the interest and favour with which American
biologists have received the theory, the six addresses on "the muta-
American ilon theory of organic evolution" delivered before the
opinion of the American Society of Naturalists at Philadelphia,
mntations December 28, 1904, may be especially referred to.
These addresses by naturalists distinguished for their
work in different phases of biology, as systematic and oecologic
botany, cytology, human anatomy, animal cecology, etc., are printed
in Science, N. S., Vol. XXI, pp. 521-543 (April 7, 1905), and from
them I quote various paragraphs indicating some of the points
of view of the speakers and some of the arguments advanced in
favour of the theory.
"On the whole, it appears that the formation of new breeds be-
gins with the discovery of an exceptional individual, or with the
production of such an individual by means of cross-breeding. Such
exceptional individuals are mutations" (Castle, p. 524).
"Modification of character by selection, when sharply alternative
conditions (i. e., mutations) are not present in the stock, is an
exceeding difficult and slow process, and its results of questionable
permanency. Even in so-called 'improved' breeds, which are sup-
OTHER THEORIES OF SPECIES-FORMING. 363
posed to have been produced by this process, it is more probable
that the result obtained represents the summation of a series of
mutations rather than of a series of ordinary fluctuating variations.
For mutations are permanent: variations transitory" (Castle, p.
"It is to my mind impossible to find any support for a theory of
evolution by minute changes from the study of anatomical varia-
tions. I should not venture to say, on the other hand, that they
give any direct support to the theory of mutation : but, at least, they
are not in disaccord with it" (Dwight, p. 532).
"It seemed necessary to discuss ethological characters at some
length for the purpose of vindicating their importance. Having
attempted this, I may say that these characters seem to me to offer
even fewer difficulties than the morphological characters to the
acceptance of the mutation theory, for the reason that the ethological
and psychological processes are conceived primarily as qualities
and not quantities. Thus the psychical elements, i. e., the simple
feelings, cravings, and sensations, are disparate qualitative processes
which cannot be derived from one another or from some more
undifferentiated process. This is still more evident in the case of the
complex psychical phenomena. Similarly, instincts, with which
ethology is most concerned, when resolved into their simplest com-
ponents are seen to consist of discrete reactions which cannot be
shown to arise from one another. Although, on the other hand,
the measurable intensities and durations of the reactions are anal-
ogous to the fluctuating structural variations, it is even more difficult
for the psychologist to conceive of a particular feeling, craving,
or sensation as arising from the greater or less intensity or dura-
tion of some other psychic process, than it is for the morphologist
to conceive of the origin of new characters from the fluctuating
variations of structure" (Wheeler, p. 539).
'"Mutation is even more urgently demanded for the explanation
of many other instincts, especially those of symbiotic and parasitic
species and of species* with profound and sudden metamorphosis.
In these cases, a particular activity, on which most often depends
the life of the individual or of its progeny, has to be performed
with a high degree of proficiency at its very phylogenetic incep-
tion or it can be of no advantage to the individual or the race.
Such cases, with which you are all familiar, have ever been the
insurmountable obstacle to the evolution of instincts on the theory
of fluctuating variations and natural selection. The theory of
organic selection seems to me merely to conceal but not to over-
come the difficulties'. The mutation theory frankly avoids the diffi-
culties even if it fails to throw any light on the origin of the muta-
364 DARWINISM TO-DAY.
tions and bundles this into the germ-plasma. It is, of course, no
objection to the theory that it leaves something under the heavens to
be accounted for. This is rather to be regarded as one of its chief
virtues. As working naturalists we have reason to be most sus-
picious of the theories that explain everything" (Wheeler, pp. 539-
"In view of the amount of orderly and well-authenticated evi-
dence now at hand, it may be regarded as demonstrated that char-
acters, of appreciable physiological value, originate, appear in new
combinations or become latent, in hereditary series of organisms,
in such a manner as to constitute distinct breaks in descent" (Mac-
Dougal, p. 540).
" Some of de Vries's experiments and observations on the La-
marck primrose have been repeated (with naturally some variation)
in the New York Botanic Garden, by MacDougal and assistants.
See MacDougal, D. T., "Mutation in Plants," Amer. Nat., Vol.
XXXVII, pp. 737-770, 1903; also, "Mutants and Hybrids of the
CEnotheras," by D. T. MacDougal, assisted by A. M. Vail,
G. H. Shull, and J. K. Small, Pub. No. 24, Carnegie Inst. of Wash.,
I am aware of the rather sweeping statements made by some
biologists touching the probability of the origin by mutation of many
species, or at least, races of animals and plants. For example,
Castle (Science, N. S., Vol. XXI, p. 522, 1905) says: "So far,
however, as these various sorts of evidence go, they indicate that
the material used by breeders for the formation of new breeds con-
sists almost exclusively of mutations." And Davenport (Science,
N. S., Vol. XXII, p. 372, 1905) says: "Undoubtedly many, if not
most, of the characteristics of the races of domesticated animals and
probably feral species have arisen by mutation." He then refers,
as example, to the qualities that differentiate the races of poultry
feathered feet, rose comb, elongated tail, taillessness, silky
feathers, frizzled feathers, cerebral hernia, polydactyl feet, albinism,
and many others. But I have been assured by Luther Burbank,
the most experienced and distinguished plant breeder in this country,
that the many races of plants actually produced by him have not
been derived from mutations. But on the contrary, that the selec-
tion of small variations a special abundance and variety of these
variations usually being induced by hybridisation and by change of
environment has been his almost exclusively relied-on means for
producing new forms of plants. As a matter of fact the cases
actually adduced by upholders of the de Vriesian theory as supports
for it are astonishingly few. Castle (Science, N. S., Vol. XXI, pp.
522-523, 1905) calls attention to the sudden appearance of a super-
OTHER THEORIES OF SPECIES-FORMING. 365
numerary fourth digit on one of the hind feet of one of nine young
produced by a certain pair of guinea-pigs. "Neither of the parents
had such a digit, nor had I ever heard of the existence of such a
character before, either in any of the wild Caviedae or among domes-
ticated cavies or guinea-pigs. Further, I have been able to find
no reference to such a thing in the literature of the group, though
I have several times since found this same mutation in other herds
of guvnea-pigs. The mother of my four-toed pig never produced
another similar individual, though she was the mother in all of
thirty young. The father, however, who sired in all 139 young,
had five other young with extra toes, but these were all by females
descended from himself, so that it seems certain that the mutation
had its origin in this particular male. By breeding together the four-
toed young and selecting only the best of their offspring, I was able
within three generations to establish a race with a well-developed
fourth toe on either hind foot. This race was not created by selec-
tion, though it was improved by that means," Castle also had
another mutation appear in a second family of guinea-pigs. "A
few individuals were found to have hair about twice as long as
that of their parents and grandparents. Intermediate conditions did
not occur. Long-haired individuals mated together were found
to produce only long-haired young, so that a new breed was already
fully established without the exercise of any selection." Casey
(Science, N. S., Vol. XXII, p. 308, 1905) presents a number of
facts touching the sudden appearance of certain molluscous genera
in early Eocene strata, and in certain Lower Oligocene rocks, which
seem to be evidence for the mutations theory. "At least, the
mutation theory is evidently the best that has been advanced to
account for these known facts." Scott (Science, N. S., Vol. XXII.
pp. 271-282) attempts to make out a case for the mutational origin
of nine kinds of North American birds that, because of their rarity
and the obscure character of the records of their occurrence, are
mostly rather puzzling to ornithologists. (They are all included
in the "hypothetical list" of the American Ornithologists' Union
Check-List.) But this attempt is robbed of much significance by
Allen's critical discussion of it (Science, N. S., Vol. XXII, pp. 431-
434, 1905). Morgan (Harper's Monthly Mag., Vol. CVI, p. 478)
refers to the "japanned" turkeys, a kind of bronze-shouldered aber-
ration that appears occasionally in flocks of turkeys, as "mutations."
These turkeys are called attention to by Darwin ("Variation of
Animals and Plants Under Domestication," Vol. I, p. 305). Indeed,
more cases of such mutations are referred to and described by
Darwin himself than by all those who have attempted recently to
adduce examples, for the support of the mutations theory, of an
366 DARWINISM TO-DAY.
alleged case of sudden appearances of modified animals or plants
that seem to breed true. But these infrequent prepotent sports,
or discontinuous variations, do little to furnish any convincing
foundation for de Vries's theory. Far better than all of them are
de Vries's own long and carefully observed primrose mutations.
Here, besides a few single mutations, were several that appeared
in considerable numbers, which is a condition almost imperatively
necessary for the successful propagation of a new organic type.
A recent record of an alleged case of mutation is Schaffner's,
"A Successful Mutant of Verbena without External Isolation," in
Ohio Naturalist, Vol. VII, pp. 31-34, December, 1906.
As Davenport ("The Mutation Theory in Animal Evolution,"
Science, N. S., Vol. XXIV, pp. 556-558, November, 1906) puts it : "The
real argument for discontinuity in evolution is the occurrence of
characteristics in nature that are discontinuous and which never
show intergrades. The mere fact of discontinuity between species
of the same genus is not sufficient to prove that they have arisen
by mutation. It must be shown that the differential characters are
in essence discontinuous. The practical way to get at the true
nature of characteristics, whether continuous or discontinuous, is
by their behaviour in inheritance. If, in cross-breeding, a char-
acter tends to blend with the dissimilar character of its consort it
must be concluded that the character can be fractionised and inter-
grades are possible. If, on the contrary, the characteristic refuses
to blend, but comes out of the cross intact, as it went in, the con-
clusion seems justified that the characteristic is essentially integral
and must have arisen completely formed, and hence discon-
"Using this criterion, I have of late been testing the application
of the mutation theory to animals and have had an opportunity to
examine the experiments of others. Some of the work has been
done on the characteristics of domesticated 'races,' others on wild
varieties. There seems to be no difference in the behaviour of
characteristics of domesticated and wild varieties. The result is
that most characteristics, but not all, fail to blend and are strictly
alternative in inheritance. I interpret this to mean that the char-
acteristic depends on a certain molecular condition that does not
fractionise. The inference is that if the characteristic is incapable of
gradations now it has always been so and hence must have arisen
without gradations, t. e., discontinuously. Examples of such discon-
tinuous characteristics are the spots in the elytra of certain beetles,
the crest on the canary, the form of the comb in poultry, extra toes,
black plumage, and colour of iris. One who sees the striking
failure of these characteristics and many others to be modified in.
OTHER THEORIES OF SPECIES-FORMING. 367
any important way will feel convinced that they are not capable
of forming intergrades and hence could not have arisen gradu-
24 C. B. Davenport ("Evolution Without Mutation," Jour, of
Exper. Zool, Vol. II, pp. 137-143, 1905), in a recent short paper,
_. , adduces facts concerning the variation and evolution
examples of spe- ^ P ectens which lead him to conclude that the races
cues-origin by of Pecten inhabiting different geographical regions
slight continu- are connected so plainly by integrating variations
ous change. t j iat t jj ere can foe n o question of mutations in con-
nection with their origin. They must have arisen through evolu-
tion by trivial variation. Davenport concludes his paper with the
following summary : "The process of evolution has taken place by
various methods and not always in the same way. It is not more