CHAP, ii The Differentiation of the Tissues 207 



description of the dermal and iascicular systems to make 

 use of a short general term for the tissues over and above 

 these, the terms Fundamental tissue, or Fundamental mass, 

 or Intercalary mass, are very suitable; just as in Naegeli's 

 treatise on the vascular bundles, or fibro- vascular masses, 

 was his distinction of these from the rest (' Proten ') or as 

 was Schwendener's general term for the parts of the vascular 

 bundle, which in his exposition of the mechanical adapta- 

 tion, did not bear upon his point. And indeed in describing 

 a form or system of whatever rank, some such method 

 must always be used. I think, however, that the distinc- 

 tion of the forms of tissue must first serve as a foundation 

 for the uniform exposition of the subject which now engages 

 us, and for the choice of terms ; then only should follow 

 the investigation how far these forms of tissue take part 

 in the formation of combinations, and systems of higher 

 rank ' (loc. cit. p. 6). 



De Bary differed fundamentally from Sachs as to the 

 basis of a classification of the tissues, claiming that the 

 latter should be founded on grounds derived from the 

 history of development. He had consequently a distinct 

 leaning to the hypothesis of Hanstein, though he admitted, 

 as we have seen, that it cannot be rigidly applied. 



De Bary's great treatise similarly was disappointing as an 

 effort in the direction of grouping the tissues in a natural 

 manner, or of dealing in a comprehensive manner with 

 their morphology. Its great merits were twofold ; it 

 gathered together an enormous mass of detail and pre- 

 sented it in orderly sequence to his readers, and it evinced 

 to a wonderful degree the critical acumen of his mind, 

 brought to bear upon many of the problems of develop- 

 ment. But to the reader who sought to obtain a coherent 

 and logical conception of general structure, it was far from 

 satisfactory, and succeeded in bewildering him with 

 multiplicity of detail rather than in giving him what he 

 sought. Anything like a satisfactory conception of general 

 anatomy was not forthcoming till Van Tieghem promul- 



