402 



PROVISIONAL HYPOTHESIS Chap. XXVII. 



previously remarked, than the retention during many ages of 

 rudimentary organs, or even only of a tendency to the production 

 of a rudiment ; but there is no reason to suppose that all dormant 

 gemmules would be transmitted and propagated for ever. Ex- 

 cessively minute and numerous as they are believed to be, an 

 infinite number derived, during a long course of modification 

 and descent, from each cell of each progenitor, could not be 

 supported or nourished by the organism. On the other hand, 

 it does not seem improbable that certain gemmules, under 

 favourable conditions, should be retained and go on multiplying 

 for a longer period than others. Finally, on the views here 

 given, we certainly gain some clear insight into the wonderful 

 fact that the child may depart from the type of both its parents, 

 and resemble its grandparents, or ancestors removed by many 



generations. 



Con elusion. 



The hypothesis of Pangenesis, as applied to the several great 

 classes of facts just discussed, no doubt is extremely complex ; 

 but so assuredly are the facts. The assumptions, however, on 

 which the hypothesis rests cannot be considered as complex in 

 any extreme degree — namely, that all organic units, besides 

 having the power, as is generally admitted, of growing by self- 

 division, throw off free and minute atoms of their contents, that 

 is gemmules. These multiply and aggregate themselves into 

 buds and the sexual elements ; their development depends on 

 their union with other nascent cells or units ; and they are capable 

 of transmission in a dormant state to successive generations. : 



In a highly organised and complex animal, the gemmules 



thrown off from each different cell or unit throughout the body 

 must be inconceivably numerous and minute. Each unit of each 

 part, as it changes during development, and we know that some 

 insects undergo at least twenty metamorphoses, must throw off 

 its gemmules. All organic beings, moreover, include many 

 dormant gemmules derived from their grandparents and more 

 remote progenitors, but not from all their progenitors. These 

 almost infinitely numerous and minute gemmules must be 

 included in each bud, ovule, spermatozoon, and pollen-gram. 

 Such an admission will be declared impossible; but, as previously 







