ORIGIN OF ORGANIC FORMS 299 



But we have already seen that, quite apart from this 

 deduction concerning the history of development, 

 geology had already demonstrated that such was the 

 chronological sequence in the appearance of these 

 groups upon our planet.^ Let us recall one of the 

 results of the preceding chapter, bearing on the im- 

 possibility of establishing any physiological border line 

 between plants and animals — the fact that the origin 

 of all organisms, the cell, or rather simply a speck of 

 protoplasm, is alike in all living beings, and we shall 

 inevitably admit the unity of the organic world, the 

 relationship, the immediate connexion between all that 

 lives on the earth. 



It may seem strange, even incomprehensible, that this 

 conclusion could have met with opposition in the face of 

 such concordant and diverse evidence from all the 

 departments of biology. We do still meet such opposi- 

 tion even to-day. 



In order to explain the origin of the divergence of view 

 among scientists, we must dwell for a short time upon 

 certain technical and perhaps tedious details, without 

 which, however, the reason for this controversy will 

 remain incomprehensible. An investigator of the organic 

 world very soon arrives at the conclusion that organisms 

 present different degrees of mutual affinity, as it is 

 generally called. In order to express the degrees of 

 affinity in the systematic description of organisms, these 

 are generally associated in groups, and the groups 

 marked by terms which indicate the degree of relation- 

 ship that exists between them ; such are the terms 

 family, genus, etc. The smallest group in which 

 the forms are most similar to each other, the group 

 which represents the collective unit, so to speak, 



■■ A recent discovery of a, distinguished English botanist, Professor 

 D. H. Scott, has proved, from the palaeontological point of view as well, 

 the connexion between ferns and the Gymnosperms in which the 

 antherozoids were found — a new triumph for Hofmeister. 



