DEVELOPMENT OF BIOLOGY 



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ests of Hooke, while Leeuwenhoek (1632-1723) of Holland spent 

 a long life studying nearly everything which he could bring within 

 the scope of his simple lenses. With an unexplored field before him, 

 all of his observations were discoveries. Bacteria, Protozoa, Hydra, 

 and many other organisms were first revealed by his lenses. But 

 Leeuwenhoek 's discovery of the sperm of animals created the most 

 astonishment. His imagination, however, outstripped his observa- 

 tions for he thought he saw evidence of the organism preformed 

 within the sperm and so regarded it as the complete germ which 

 had only to be hatched by the female. (Figs. 14, 26, 292.) 



Fig. 292. — Antony van Leeuwenhoek. 



The patience and ingenuity of Leeuwenhoek was equalled, if not 

 exceeded, in the studies on insect anatomy made by Swammerdam 

 (1637-1680) of Holland. Inspired largely by the desire to refute 

 the current notion that Insects and similar lower animals are with- 

 out complicated internal organs, Swammerdam spent his life in 

 studies on their structure and life histories. Revealing, as he did, 

 by the most delicate technique in dissection, the finest details 

 observable with his lenses, Swammerdam not only set a standard 

 for minute anatomy which was unsurpassed for a century, but also 

 dissipated for all time the conception of simplicity of structure in 

 the lower animals. He thus, quite naturally, added one more 

 argument to those of the Italian Redi (1626-1698) and others 



