DIVISION OF THE VEGETABLE CELL. 27 



or consistence, we may conclude that in instances such as some of 

 the Amoebae, where they appear little denser than the medium in 

 which they live, we have not protoplasm only, but protoplasm 

 plus water ; and such being the case, there would seem to be no 

 reason for concluding, from its physical constitution, that the idea 

 of its possessing structure is inconceivable. 



When, however, we pass from such considerations as these and 

 look at the infinite variety of life forms, both animal and vegetable, 

 with all their varied functions and capacities, and remember that 

 they each and all had their origin in a microscopic mass of this 

 protoplasm ; the thought that for them all this substance from which 

 they arise is absolutely alike is to say the least difficult of belief. 

 Dr. Allman, in his presidential address before the British Associa- 

 tion in 1879, deals with this question in a most forcible manner 

 when he says, " To suppose, however, that all protoplasm is iden- 

 tical where no difference is cognisable by any means at our disposal 

 would be an error. Of two particles of protoplasm, between which 

 we may defy all the powers of the microscope, all the resources of 

 the laboratory, to detect a difference, one can develop only into a 

 jelly fish, the other only to a man, and one conclusion alone is here 

 possible : that deep within them must be a fundamental difference, 

 which thus determines their inevitable destiny, but of which we 

 know nothing, and can assert nothing, beyond the statement that 

 it must depend on their hidden molecular constitution." " In the 

 molecular condition of protoplasm there is probably as much com- 

 plexity as in the disposition of organs of the most highly differen- 

 tiated organisms ; and between the two masses of protoplasm in- 

 distinguishable from one another, there may be as much molecular 

 difference as there is between the form and arrangement of organs 

 in the most widely sepraated animals or plants." Certainly this 

 view of the question could not possibly be presented in a better 

 form, but it may perhaps help us to realize how extremely probable 

 this is if we remember into what diversified products the same ele- 

 mentary substances combining in the same proportions give rise. 

 We have already seen that cellulose, sugar, starch, and inulin, are 

 isomeric with each other, that is, that the elements and combining 

 proportions are the same in each case, although they possess such 

 very different physical characteristics. A far more remarkable 

 exaurple is, that in twenty-seven volatile oils, including those of 

 chamomile, hops, turpentine, clove, lemon, valerian ; the carbon 



