146 The Science of Life. 



Brooks shares, there are several subsidiary hypotheses 

 in the modification which he has proposed. It is in 

 unwonted and abnormal conditions that the cells of the 

 body throw off gemmules; the male elements are the 

 special centres of their accumulation; it is the ovum 

 that keeps up the general resemblance between offspring 

 and parent. 



The theory of " Pangenes" advocated by De Vries in 

 1889 is hardly in any sense a rehabilitation of Darwin's, 

 since it rejects the hypothesis of " transport", and in- 

 corporates the distinctively modern conception of ger- 

 minal continuity. It has often been urged that the 

 hypothesis of pangenesis involves not one but many 

 suppositions that it is just as difficult to understand 

 why a gemmule should reproduce a cell like its own 

 origin as to understand the entire problem, and so on. 

 Detailed criticism will be found in the works of Galton, 

 Ribot, Brooks, Herdman, Plarre, and others. It is 

 enough to emphasize the comparative gratuitousness of 

 any special theory whatever, a paradox which is ex- 

 plained in the succeeding section. 



As far back as 1849 Owen pointed out in his paper 



on Parthenogenesis that in the developing germ it was 



The Doctrine P oss il e to distinguish between cells which 



of Germinal became much changed to form the body, 



ontinuity. and CGl{s wh[ch remained little changed and 



formed the reproductive organs. This was probably 

 the earliest distinct suggestion of the modern theory of 

 germinal continuity, but Owen seems to have virtually 

 abandoned it later on. 



In 1866, in his classic Generelle Morphologie, Haeckel 

 emphasized the simple and yet fundamental fact of the 

 material continuity of offspring and parent. In a his- 

 torical note upon the distinction between the " personal" 

 and "germinal" parts of an organism, Rauber states 

 that the distinction was proposed by Haeckel in 1874, 

 and by himself in 1879. 



Jaeger stated the doctrine of germinal continuity 

 very clearly and concisely at an early date (1878): 

 "Through a great series of generations the germinal 

 protoplasm retains its specific properties, dividing in 



