136 SCIENCE AND PHILOSOPHY OF THE ORGANISM 



It is clear, that by taking away any part of the original 

 system, by means of operations, there would be taken away 



a certain amount of the original compound ; say that - 



n 



is left; then, of course, the three constituents after the 



partial disintegration would be -, - and -, and so it 



n n n 



follows that the proportionality of localisation would really 

 be preserved in any case. 



But these considerations, evident as they seem to be in 

 the most simple case, fail to satisfy in a really general 

 sense : for two different reasons. First, they could never 

 account for the fact that the differentiated organism by no 

 means consists of so many different compounds as it shows 

 single parts of its differentiation, but that, on the contrary, 

 it only consists, as we know, of a certain rather limited 

 number of true different morphogeuetic elements, these 

 elements occurring again and again as for instance, nervous 

 or muscular elements but typical each time in locality, 

 quantity, and form. And in the second place, the very 

 form of elementary organs, their form as such, does not at 

 all go hand-in-hand with chemical differences ; this feature 

 alone would absolutely overthrow any sort of a chemical 

 morphogenetic theory to account for the problem of 

 localisation. Take the typically arranged ring of the 

 mesenchyme cells in our Echinus-gastrula, with its two 

 spherical triangles, so typically localised ; look at any sort 

 of skeleton, in Eadiolaria, or in starfishes, or in vertebrates : 

 here you have form, real form, but form consisting of only 

 one material. Not only is the arrangement of the elements 

 of form typical here, e.g. the arrangement of the single 



