No. 554] SHORTEE ARTICLES AND DISCUSSION 1 23 



A LITERARY NOTE ON THE LAW OF GERMINAL 

 CONTINUITY 



The distinctive theory of germinal continuity or continuity 

 of the germ-plasm is, historically speaking, of much more recent 

 origin that the broader doctrine of genetic continuity from 

 which it was derived and with which, in the usage of some 

 writers, it is made synonymous. Genetic continuity in its 

 widest sense embodies the proposition that '•' living matter 

 always arises by the agency of preexisting living matter," 1 

 and in a more restricted sense means that all living cells must 

 be derived by continuous lineage from the cells of preexisting 

 generations. The theory of germinal continuity, in its most 

 highly developed form, conceives the germinal protoplasm as 

 dividing into two portions, from one of which the somatic or 

 body cells of the offspring are developed while the other portion 

 is reserved unchanged for the formation of the reproductive 

 material of the adult individual. The general doctrine of con- 

 tinuity is fundamentally essential to both these theories, but 

 germinal continuity, at least in any Weismannian sense, always 

 involves the further assumption of a transmission from genera- 

 tion to generation of an unmodified residue of the specially 

 organized germinal substance, the germ-plasm, through a defi- 

 nite series of cells, but this concept does not imply that there is 

 necessarily a direct connection between the germ-cells of con- 

 secutive generations. 



To Richard Owen the credit is usually given of being the 

 first to recognize the distinction between body-cells and germ- 

 cells and thus to foreshadow the idea of germinal continuity. 

 Writing in 1849, he said: 



Not all the progeny of the primary impregnated germ-cell are re- 

 quired for the formation of the body in all animals: certain of the 

 derivative germ-cells may remain unchanged and become included in 

 that body which has been composed of their metamorphosed and 

 diversely combined or confluent brethren: so included, any derivative 

 germ-cell or the nucleus of such may commence and repeat the same 

 processes of growth by imbibition, and of propagation by spontaneous 

 nssion, as those to which itself owed its origin: followed by meta- 

 morphoses and combinations of the germ-masses so produced, which 

 concur to the development of another individual ; and this may be, or 



'Huxley, T. H., "Lav Sermons, Addresses and Reviews," New York, 

 18 70, p. 350 



