X.] PAXGENESIS. 



difficult to understand is the process of the stomach- 

 carrying-off mode of metamorphosis before spoken of as 

 existing in the Echinoderms, Next, as to certain patent 

 and notorious facts : On the hypothesis of pangenesis, no/ 

 creature can develop an organ unless it possesses the; 

 component gemmules which serve for its formation. No ' 

 creature can possess such gemmules unless it inherits them 

 from its parents, grandparents, or its less remote ancestors. 

 Now, the Jews are remarkably scrupulous as to marriage, 

 and rarely contract such a union with individuals not of 

 their own race. This practice has gone on for thousands 

 of years, and similarly also for thousands of years the rite 

 of circumcision has been unfailingly and carefully performed. 

 If then the hypothesis of pangenesis is well founded, that , 

 rite ought to be now absolutely or nearly superfluous from 

 the necessarily continuous absence of certain gemmules 

 through so many centuries and so many generations. Yet 

 it is not at all so, and this fact seems to amount almost 

 to an experimental demonstration that the hypothesis of 

 pangenesis is an insufficient explanation of individual evo- 

 lution. 



Two exceedingly good criticisms of Mr. Darwin's hy- 

 pothesis have appeared. One of these is by Mr. G. H. 

 Lewes, 4 the other by Prof. Delpino of Florence. 6 The latter 

 gentleman gives a report of an observation made by him 

 upon a certain plant, which observation adds force to what 

 has just been said about the Jewish race. He says : 6 " If 

 we examine and compare the numerous species of the 

 genus Salvia, commencing with Salvia officinalis, which 

 may pass as the main state of the genus, and concluding 



4 See Fortnightly Review, New Series, vol. iii., April, 1868, p. 352. 



5 This appeared in the Revista Contemporanea Nazionale Italiana, and 

 was translated and given to the English public in Scientific Opinion for 

 September 29, October 6, and October 13, 1869, pp. 365, 391, 407. 



6 See Scientific Opinion, of October 13, 1869, p. 407. 



