CHAPTER IX 



INVERTEBRATE RESEARCH IN THE EIGHTEENTH CENTURY 



Successors of the great seventeenth-century biologists 



THE EIGHTEENTH CENTURY displays OH the whole great activity in the 

 sphere of the natural sciences. In physics and chemistry the successors 

 of Newton and Stahl worked at extending the spheres to which 

 their masters had opened the way. In the realm of biology Linnasus and his 

 disciples held sway and were fully occupied in incorporating known species 

 into the system and in discovering fresh ones. As already mentioned, Buffon's 

 activities belonged rather to the future. But besides this there worked during 

 the eighteenth century a number of naturalists whose achievements connected 

 them more or less directly with the great biologists of the preceding century. 

 Towards these pioneer anatomists, microscopists, and physiologists their 

 successors during the eighteenth century have to some extent the character of 

 Epigoni: they made no such epoch-making discoveries as Harvey's or Mal- 

 pighi's, but, on the other hand, they took advantage in many and various 

 ways of the discoveries that had already been made; the problems which 

 had already been of direct importance were discussed from various points of 

 view, while at the same time ideas were expressed in more than one field of 

 research which gave a presage of future ends to be gained. Malpighi's and 

 Swammerdam's investigations into the anatomy of the lower animals were 

 thus resumed and carried a step further, as also Borelli's and his successors' 

 physiological work; Leeuwenhoek's and de Graaf's discoveries in the field 

 of reproduction were elaborated, and the discussion between the animalcul- 

 ists and the ovists went on, particularly in the first half of the eighteenth 

 century, with undiminished liveliness; the epigenesis and preformation theo- 

 ries were also keenly debated, although at first with the balance decidedly 

 in favour of the supporters of preformation. Later in the century, however, 

 contributions were made in these very spheres which put a different complex- 

 ion on those questions. And even for several other spheres of biology the 

 latter half of the eighteenth century represents a period of decisive prepara- 

 tion for the development that took place during the nineteenth century. — 

 In the following paragraphs we shall review, to begin with, some of the 

 more important contributions to the biology of the lower animals, and 

 afterwards the advances made in the spheres of anatomy, physiology, and 

 evolution. 



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