496 THE POPULAR SCIEXCE MONTHLY. 



brief reference here made, but tlie perusal of it will certainly impress 

 one with the profound change which has taken place in the method of 

 treating a subject of this nature comjiared to the treatment it might 

 have received in pre-Darwinian days. Indeed, the features discussed 

 in this paper would not have attracted a moment's attention from the 

 older naturalists. 



Since Darwin published his provisional theory of Pangenesis it has 

 provoked speculative efforts on the part of some of our naturalists to 

 devise other hypotheses which might answer some of the objections 

 urged against Darwin's hypothesis. Space will permit only a mention 

 of a few of these papers. Professor W. K. Brooks * presented, in 

 brief abstract, at the Buffalo meeting eleven years ago, a provisional 

 theory of Pangenesis. These views, more elaborated, are now pub- 

 lished in book-form, under the title of " The Laws of Heredity." An 

 illustrious reviewer says it is the most important contribution on the' 

 speculative side of Darwinism that has ever appeared in this country, 

 lie has also aptly termed studies of this nature molecular biology. Dr. 

 Louis Elsberg at the same meeting also read a paper on the plasti- 

 dule hypothesis. 



Dr. John A. Ryder f has made an interesting contribution entitled 

 " The Gemmule versus the Plastidule as the Ultimate Physical Unit 

 of Living Matter." In this paper he discusses Darwin's provisional 

 theory of Pangenesis, and shows it to be untenable from Galton's ex- 

 periments. 



Haeckel's provisional hypothesis of the perigenesis of the plasti- 

 dule is clearly stated, and he closes by saying that the logical conse- 

 quences of the acceptance of Haeckel's theory, and with it the theory 

 of dynamical differentiation — because the latter is no longer an hy- 

 pothesis — forever relegate teleological doctrines to the category of ex- 

 tinct ideas. 



The wide-spread public interest in Darwinism arose from the fact 

 that every theory and every fact advanced in proof of the derivative 

 origin of species applied with equal force to the origin of man as one 

 of the species. The public intei-est has been continually excited by 

 the consistent energy with which the Church — Catholic and Protestant 

 alike — has inveighed against the dangerous teachings of Darwin. 

 Judging by centuries of experience, as attested by unimpeachable his- 

 torical records, it is safe enough for an intelligent man, even if he 

 knows nothing about the facts, to accept promptly as truth any gen- 

 eralization of science which the Church declares to be false, and con- 

 versely to repudiate with equal promptness as false any interpretation 

 of the behavior of the universe which the Church adjudges to be true. 

 In proof of this sweeping statement, one has only to read the impos- 



* "Proceedings of the American Associated Antiquarian Society," vol. xxr, p. Ill; 

 also " American N.ituralist," vol. xi, p. 144. 

 f " American Naturalist," vol. xiii, p. 12. 



