334 THE HISTORY AND SCOPE OF ZOOLOGY IX 



Province: Radiata. 



Sub-Province: Radiaria. 



Classes : ECHINODERMATA, BRYOZOA, ANTHOZOA, ACA- 



LEPH^:, HYDROZOA. 

 Sub-Province : EntOZOa. 



Classes : CCELELMINTHA, STERELMINTHA. 

 Sub-Province : Infusoria. 



Classes : ROTIFERA, POLYGASTRIA (the Protozoa of recent 

 authors). 



The real centre of progress of systematic Zoology 

 was no longer in France nor with the disciples of 

 Cuvier in England, but after his death moved to 

 Germany. The wave of morphological speculation, 

 with its outcome of new systems and new theories of 

 classification, which were as numerous as the pro- 

 fessors of zoological science/ was necessarily succeeded 

 in the true progress of the science by a period of 

 minuter study in which the microscope, the discovery 

 of embryological histories, and the all-important cell- 

 theory came to swell the stream of exact knowledge. 



We have already mentioned Von Baer in this 

 connection, and given a passing reference to Johann 

 Mtiller, the greatest of all investigators of animal 

 structure in the present century. Mliller (1801-1858) 

 was in Germany the successor of Eathke (1793-1860) 

 and of Meckel (1781-1833) as the leader of anatom- 

 ical investigation ; but his true greatness can only be 

 estimated by a consideration of the fact that he was a 

 fertile teacher not only of human and comparative 

 Anatomy and Zoology but also of Physiology, and 

 that nearly all the most distinguished German 

 zoologists and physiologists of the period 1850 to 



1 See Agassiz, Essay on Classification, 1859, for an account of them. 



