ON THE MORPHOLOGICAL VIEW OF NATURE. 227 



scale. 



the great revolution of ideas which the seventeenth 

 century witnessed was much assisted by the invention 24. 



Morphology 



of the telescope and founded upon its revelations, the ? o f o minnte 

 change of thought during the nineteenth century has 

 been connected more with the revelations of the 

 microscope. The great movement of ideas started by 

 Galileo, and continued through Kepler, Newton, and 

 Laplace, was accompanied by the perfection of the 

 telescope. The invention of the microscope enabled 

 Nehemiah Grew and Malpighi to begin half a century 

 later their embryological studies, and to inaugurate a 

 line of research which, in our days, through a long series 

 of observations x from Amici to Strasburger on the pro- 



1 These observations begin with 

 the year 1830, when Amici, to 

 whom great improvements in the 

 microscope are due, " traced the 

 pollen grain from its lighting on 

 the carpel tip down into the 

 recesses of the ovule " (Geddes and 

 Thomson, ' The Evolution of Sex,' 

 p. 140), and removed all doubts 

 And uncertainty by his observa- 

 tions on orchids in 1845 and 1846. 

 " Here he demonstrated the whole 

 series of processes, from the pollen 

 dust on the stigma to the for- 

 mation of the embryo" (Sachs, 

 'Gesch. d. Botanik,' p. 469). 

 About the same time (1843) Martin 

 Barry " observed the presence of 

 the sperm within the ovum in the 

 rabbit ovum " (Geddes and Thom- 

 son, loc. cit., p. 142). It took, how- 

 ever, a quarter of a century, from 

 the first discovery of Amici, before 

 the process of fertilisation described 

 by him was accepted by embryo- 

 logists as typical for both plants 

 and animals. Bischoff, the great 

 authority in Germany, after con- 

 firming the entrance of the sperm- 

 cell into the ovum, maintained by 



Barry in 1843, and by Newport 

 (with frogs) in 1851 and 1853, ex- 

 presses his "infinite astonishment," 

 adding that "Dr Barry is certainly 

 the first who has seen a sper- 

 matozoon in the interior of any 

 ovum, and notably in the ovum of 

 a mammal, and that to him be- 

 longs the glory of this discovery " 

 (Theod. Bischoff, ' Bestatigung des 

 von Dr Newport bei den 

 Batrachiern und Dr Barry bei 

 den Kaninchen behaupteten Ein- 

 dringens der Spermatozoiden in 

 das Ei,' 1854, p. 9). For the 

 history of scientific thought it is 

 significant to see how little, even 

 in the middle of the century, dis- 

 coveries referring to the phenom- 

 ena of plant life or structure were 

 known or utilised by students of 

 animal life. A mutually fructify- 

 ing influence seems to date like 

 so many other advances from the 

 publication, in 1859, of the ' Origin 

 of Species.' "The distinctively 

 modern era in the history of 

 fertilisation dates from about 1875, 

 when the brilliant researches of 

 Auerbach, Van Beneden, Biitechli, 



