58 HAECKBL 



female ovum was a cell. They melted together 

 and were blended into a new cell in the act of 

 procreation, and from this, by a process of repeated 

 cleavage of cells, the new individual was developed 

 with all his millions of cells and all the elaborate 

 tissues that these cells united to form. A whole 

 world of marvellous features came to light, but the 

 key to the unriddling of them was still wanting. 



However, the Wiirtzburg school was at least 

 agreed as to method, which was the main thing ; 

 its leaders were determined to press on to the 

 solution of these problems on purely scientific 

 lines. Everything was to be brought into a 

 logical relation of cause and effect, and there 

 was to be no intrusion of the supernatural, no 

 mysticism. Natural laws must be traced in the 

 life of the cells and in the history of the ovum 

 and the embryo. The cells were to be regarded 

 in the same way as the astronomer regards his 

 myriads of glittering bodies. In this way the 

 science of histology had been founded, and 

 embryology had assumed a scientific character 

 in the hands of Von Baer. The microscope kept 

 the attention of students to facts, and did not 

 suffer them to lose themselves in the clouds. 

 Thus a foundation-stone was laid in Haeckel's 

 thoughts which he would never discard. 



In the later years of the Darwinian controversy 

 he was destined to come into sharp conflict with 

 both Virchow and Kolliker. Each of them came 

 to look on him as the sober hen does on the 

 naughty chick it has brought into the world, 



