248 THE INDUCTIONS OF BIOLOGY. 



greater bulk and organization. Hence it would be impossible 

 to say where the lower individualities ceased and the higher 

 individualities commenced. 



§ 73. To meet these difficulties, it has been proposed that 

 the whole product of a single fertilized germ shall be re- 

 garded as a single individual; whether such whole product 

 be organized into one mass, or whether it be organized into 

 many masses that are partially or completely separate. It 

 is urged that whether the development of the fertilized germ 

 be continuous or discontinuous (§50) is a matter of secondary 

 importance; that the totality of living tissue to which the 

 fertilized germ gives rise in any one case, is the equivalent of 

 the totality to which it gives rise in any other case ; and that 

 we must recognize this equivalence, whether such totality 

 of living tissue takes a concrete or a discrete arrangement. 

 In pursuance of this view, a zoological individual is consti- 

 tuted either by any such single animal as a mammal or bird, 

 which may properly claim the title of a zoon, or by any such 

 group of animals as the numerous Medusce that have been 

 developed from the same egg, which are to be severally dis- 

 tinguished as zooids. 



Admitting it to be very desirable that there should be 

 words for expressing these relations and this equivalence, it 

 may be objected that to apply the word individual to a num- 

 ber of separate living bodies, is inconvenient : conflicting so 

 much, as it does, with the ordinary conception which this word 

 suggests. It seems a questionable use of language to say that 

 the countless masses of Anacharis Alsinastrum (now Eloidea 

 canadensis) which, within these few years, have grown up in 

 our rivers, canals, and ponds, are all parts of one individual : 

 and yet as this plant does not seed in England, these count- 

 less masses, having arisen by discontinuous development, 

 must be so regarded if we accept the above definition. 



It may be contended, too, that while it does violence to 

 our established way of thinking, this mode of interpreting 



