Mar., 1905.] 



KNOWLEDGE & SCIENTIFIC NEWS. 



51 



third of these remained recessive in all subsequent genera- 

 tions. And still continuing- his experiments with the 

 remaining^ fifty per cent., he found they g^ave recessive 

 and dominant characters in the same proportions as 

 in earlier generations. 



In recent years many sets of experiments have been 

 made to test Mendel's results, and Mr. W. Bateson 

 has initiated a movement for the thorougfh further 

 investigation of the subject experimentally, whilst, on 

 the other hand, a school of biologists led by Professor 

 W'eldon, who have been applying the mathematical 

 methods for solving the difficult problems of heredity, 

 contend that the results obtained by Mendel do not 

 accord with the mathematical laws as worked out h\ 

 those following the lines of enquiry laid down by Gal- 

 ton. These differences in the results obtained by the 

 two schools of biologists are giving rise to much con- 

 troversy, but the history of science is rich in instances 

 in which investigations giving apparently discordant 

 results have led up to import-ant additions to our 

 knowledge. We have very good ground for hoping 

 that, in the near future, very important further steps 

 may be made in this direction for placing our know- 

 ledge of this important subject upon a scientific basis. 

 A problem of great interest which has provoked 

 much discussion in recent years, is the question 

 whether characters which have been acquired during 

 the life of an individual are transmitted to its off- 

 spring. Darwin under the title of " Use and Disease," 

 admits it as possible that the power of flight possessed 

 by wild ducks may have been lost by tame ducks in 

 consequence of disuse. In more recent years, Weis- 

 mann has convinced himself that characters of this 

 nature are not transmitted to the offspring. The 

 blacksmith's arms become abnormally developed in the 

 exercise of his calling; but no instance has been re- 

 corded in which blacksmiths' children were endowed 

 with any special development of the muscles of their 

 arms. The feet of Chinese women have been artifici- 

 ally distorted for ages, but they will still develop to 

 natural proportions if permitted to do so. The loss 

 of power of flight by tame ducks is best explained by 

 the survival of those varieties with small powers of 

 flight, under artificial conditions, being favoured by 

 selection, whilst in the wild state the birds with great 

 power of flight can best escape from their enemies. 

 There is, however, another description of acquired 

 character, which cannot be finally dismissed without 

 further investigation. Some keepers and others ex- 

 perienced in training dogs for sport are convinced 

 that the offspring of dogs which have been trained 

 can invariablv be broken in with much less trouble 

 than the offspring of dogs from equally good stock 

 which had been kept as domestic pets. A naturalist 

 friend of mine who has kept various species of mice 

 in confinement, assures me that whilst the progeny 

 of white mice, whose ancestors have been kept for 

 many generations as pets, in their earliest stage of 

 growth show little fear of man — though we have no 

 evidence of this characteristic having been favoured by 

 selection — the offspring of the field-mouse, as soon as 

 it can run, will scamper off on the approach of man. 

 It is difficult to explain the peculiar habits of the 

 cuckoo, unless they were acquired at some early 

 period. The solitary wasp, which, like the cuckoo, 

 never knows its parents, constructs a nest or cell in 

 which it stores small caterpillars, injured but not 

 killed, and hangs its eggs well out of risk of damage 

 by the caterpillars, so that when the e§^ hatches the 

 grub may find a plentiful store of fresh meat at hand. 



Many similar examples occur amongst fishes and in- 

 sects. And until we can satisfy ourselves that these 

 animals, fishes, and insects have sonic means of com- 

 municating with one another in mature life, or until 

 it has been shown how such habits can arise without 

 having been acquired, it is difficult to dismiss al- 

 together the inheritance of acquired characters as im- 

 possible. Professor Herring, in an address upon 

 heredity, delivered at the Imperial Academy of 

 Sciences, Vienna, May 30th, 1870, suggested that as 

 it is noteworthy that every act of our daily lives is due 

 to unconscious memory, the power of memory may be 

 the property of all organised matter, and that it may be 

 tiansmitted from one generation to another through 

 the germ-cell. This problem should not be beyond the 

 reach of experiment, and if established might not only 

 explain these obscure phenomena, but many others, 

 both in the vegetable and animal kingdom : the 

 power possessed by roots of penetrating the soil, avoid- 

 ing light and air; the habit of some flowers of poking 

 their seed-vessels into crevices in rocks and walls or 

 burying them in the ground; the habit of sun-dews of 

 closing their glandular hairs when stimulated by insect 

 prey; periodicity, so frequent in animals and plants, as, 

 for instance, the opening of those flowers which require 

 day-flying insects to convey their pollen from plant to 

 plant in the morning, whilst those flowers which rely 

 upon night-flying insects for this duty open in the even- 

 ing; and many other similar phenomena. The possi- 

 bility that the transmission of the power of memory 

 from one generation to another may play some part in 

 transmitting such habits should not be entirely dis- 

 missed until it has been tested by careful experimental 

 investigation. 



Other phenomena of heredity not having advanced 

 since the pre-Darwinian days, we must proceed to con- 

 sider the possible application of a greater knowledge 

 of the subject to the benefit of mankind. Tlie appli- 

 cation of well-established rules by the breeder of ani- 

 mals and by horticulturists is too obvious to dwell 

 upon. Already racing and draught horses, fat cattle, 

 sporting dogs, brilliant flowers, luscious fruit, and 

 other things demanded by men are attained by the 

 practical man almost to order; nevertheless, an exact 

 knowledge of the laws underlying these industries 

 might bring about as great a revolution as that which 

 has been accomplished in fields of activity by the ap- 

 plication of principles of physical science. But a 

 question of even greater importance remains. What 

 eft'ect will a more exact knowledge of these laws have 

 upon the human race itself? 



Xt a recent meeting of the Sociological Society, 

 allusions were made to the " false social standard " 

 and to the indiscriminate attachments by men and 

 women. It was suggested that a wider diffusion of 

 a knowledge of the laws of heredity "would bring in- 

 fluence to bear upon marriages." Sound knowledge 

 of the scientific laws underlying the phenomena of 

 nature has had a most beneficent effect upon 

 humanity in the past, and any addition to our know- 

 ledge will undoubtedly be valuable in the future, yet 

 the sober student must find some difficulty in fore- 

 telling the direct effect of an extension of our know- 

 ledge of heredity upon the races of men. It is diffi- 

 cult to conceive by what system of exact measure- 

 ments we could estimate the subtle and innumerable 

 physical and mental traits which go to the making of 

 a Napoleon, a Bismarck, or a Darwin. 



Sir Edwin Arnold foretold the destiny of the 

 Japanese race, at a time when they were ree-arded by 



