178 THE POPULAR SCIENCE MONTHLY. 



Sarah, who sought to excuse the illegitimacy of her child by the 

 plea that " it was a very little one." In his reply to Mr. Herbert 

 Spencer's articles * he has made matters worse by explaining it 

 on the supposition that "spermatozoa occasionally reach the 

 ovary, and there enter into some of the immature eggs. Am- 

 phimixis can not proceed, as the germ-plasm of the egg is not ripe, 

 but the nucleus of the sperm cell continues to live in certain cir- 

 cumstances, and so remains till the time of a subsequent coitus 

 with another mate/' f 



It is obvious that in such a case the " subsequent coitus " need 

 have nothing to do with the matter ; whenever the egg was ripe 

 there would be nothing to prevent amphimixis taking place, fol- 

 lowed by all the stages of ontogeny, and we should have a case of 

 parthenogenesis in the mammalia. If this were possible in the 

 human race it would create something of a ripple in the social 

 world. 



Prof. Weismann does not deny that certain diseases, especially 

 germ diseases, are hereditary and directly transmissible in the 

 first instance, and he admits that this has " definitely been proved 

 to occur in the case of syphilis. The father, as well as the mother, 

 is capable of transmitting this disease to the embryo, and the 

 only possible explanation of this fact is, therefore, that the spe- 

 cific bacteria of syphilis can be transmitted by the spermato- 

 zoon." I But he will not admit that this constitutes a case of the 

 transmission of acquired characters, undertakes to connect it with 

 the adaptation of the parasite to the host, and concludes : 



" It will, I think, at any rate be conceded that a ' constitutional ' 

 disease can not be taken as a proof that the processes of heredity 

 are therein concerned until we can determine whether we are 

 actually dealing with heredity i. e., the transmission of a consti- 

 tution and not only with a transference of microbes." * 



This all seems very absurd to the average reader, and conveys 

 the impression that the scientific discussion of these questions has, 

 after all, no interest for the public, and only amounts to a useless 

 hair-splitting on the part of the doctors. For what matters it to 

 the consumptive whether his case is one of " the transmission of a 

 constitution " or " the transference of microbes " ? Mr. Spencer, in 

 the articles above referred to, has sufficiently characterized the 

 reasoning which allows a microscopically visible microbe to pene- 



* The Inadequacy of " Natural Selection." Contemporary Review for February, March, 

 and May, 1893; reprint, London, Williams & Norgate ; New York, D. Appleton & Co., 

 1893, p. 69. 



f The All-sufficiency of Natural Selection. A Reply to Herbert Spencer. Contemporary 

 Review for September and October, 1893, p. 609. 



J The Germ-Plasm, p. 388. * Ibid., p. 391. 



