MISCELANEOUS.

Inangahua Times, Volume IX, Issue 1359, 8 February 1884, Page 2

MISCELANEOUS.

' ■♦ ■ The profoundest problem of the 1 present age is heredity. By that terra is not meant such tricks as Jacob, played upon Laban by which the thrifty young patriarch increased his share in the community flocks; nor the judicious selection of stockbreeders whereby the fine points or variations, in hoi«ees and cattle are perpetuated and made typical of favourite strains ; nor yet the careful mating of birds togive colour to a feather which establishes the reputation of a poultry yard ► The question has deeper signification! than these mere commercial considerations, and seeks not the facts of transmission which are patent to all, but rather those ultimate causes and processes which determine life and itsdirection ; the reason, for instance, why three eggs scooped from the seaand subjected to identical conditions develop one into a star-fish, another into a crustacean, and the third into a vertebrate. What causes persistence of organic forms, and what are thoseinfluences that produce variations which gradually develop into new species? To these and kindred questions science from the days of Aristotle to Herbert Spencer has 'applied itself, and, it must be confessed, with, so far little satisfactory result The last, contribution to the literature of the subject (says the San BYancisco Bulletin) is from the assistant in biology at the John Hopkins University, W, K. Brooks, who puts forth what he calls a "new theory of heredity," and which he claims has points of contact with the conflicting theories of Aristotle, Bonnet, Haller, B'uffon, Jager, •Haeckel and Darwin, and yet offers a» explanation of many factors in theproblem which those eminent biologists have left unsolved. Mr Brooks' condensed statement of his theory on pages 81, 84, and 85, is too long for quotation, but may be summarised as follows : — The union of two sexual elements gives variability. In multicelfolar organisms, the ovem and themale cell have become specialised in different directions. The ovum has acquired a complicated organisation and contains particles to correspond toeach of the hereditary characteristics; of the species. The ovum is able to* give rise to the divergent cells of the organism and to cells like itself. Theovarium ova of the offspring are these latter cells or their unmodified descendants. Each cell of the body has power to grow ; to give rise to similar cells and to throw off minute germs. During the evolution of the species r it has acquire^, by natural selection, distinctive functions which are adapted to the conditions under which it is placed. £>o long as theseconditions remain unchanged it performs its proper functions as a part of the body, but when, by change of environment, its fouction'ls 'disturbed,, it throws off particles which are the *• gemmules" of this particulal celL These gemmules may, be carried to all •parts of the body. The male cell has: acquired a peculiar power to gather and store these germs. When the ovum is fertilised each gemmule unites with that particle of the ovum which is destined togive rise in the offspring to the cell corresponding to the one which produced thegerm ; orunites with a closely related, particle, destined to produce a closelyrelated cell. This cell developed in the body of the offspring is a hybrid,, and tends to vary. The ova of the offspring will also tend to vary, and the cells thus varied will throw off gem mulesand thus transmit variability to successive generations of descendants till a favourable variation is seized upon by natural selection. When the variation becomes an hereditary race characteristic, it will be perpetuated and transmitted without gemmules. For the illustration and demonstration of these propositions the book is written. The author has little expectation of his views being permanently accepted! as now presented, but hopes they will serve to stimulate thought and experiment in this interesting department of scientific research. The field is broad and there is room for many workers. Whether the secret of Nature in this direction will ever be discovered it is impossible to predict. If done it will only be by patient and delicate experimenting, and it seems to us that in this and other lines of original investigation lies one of the opportunities of the great universities. They ought to provide the -moneyy the apparatus, and the trained assistants which the investigator needs, and which are far beyond his private means. But universities have only that which is given to disburse, and so it resolves itself back to the question whether tn& people through their Legislatures, or rich men who desire to leave some permanent memory of themselves, shall endow such departments.