PULLULATION IN THE GENETIC CYCLE. V 155 



which the pullulation seems to lie out of the primary cycle 

 of propagation altogether. So it is in plants, with what 

 Braun calls the "inessential sprouts," that is, shoots over 

 and above those which are necessary to the full carrying out 

 of the series of formations up to blossom and fruit. These 

 inessential shoots are mostly formed subsequently to those 

 essential to the cycle, and in some species are very numerous 

 and regular, constituting the great mass of the vegetation, 

 and enabling the plant to rise up in new generations from 

 the same stock, year after year, and thus repeatedly to pro- 

 duce flower and fruit ; or, again, they may become detached, 

 and serve the purpose of dispersing the plant.* We have 

 phenomena of a like kind among animals also, both in the 

 growth of the ramose polypidoms, and in the reversion of 

 the " Hydra Tuba' to the gemmation of common polype- 

 buds, after having thrown off swarms of Medusa-buds. ~f* 



* Rejuvenescence, p. 36. 



t Dalzell's Remarkable Animals of Scotland, Vol. I., ch. 3. Dr. J. 

 Reid's Anat. and Physio 1 . Researches, pp. 652-656. 



