A Century of Science 17 



grand classification of animals in space and time 

 which at once cast into the shade all that had gone 

 before it. During the past fifty years there have 

 been great changes made in Cuvier's classification, 

 especially in the case of the lower forms of animal 

 life. His class of Hadlata has been broken up, 

 other divisions in his invertebrate world have been 

 modified beyond recognition, his vertebrate scheme 

 has been overhauled in many quarters, his attempt 

 to erect a distinct order for Man has been over- 

 thrown. Among the great anatomists concerned 

 in this work the greatest name is that of Huxley. 

 The classification most generally adopted to-day is 

 Huxley's, but it is rather a modification of Cuvier's 

 than a new development. So enduring has been 

 the work of the great Frenchman. 



With Cuvier the analysis of the animal organ- 

 ism made some progress in such wise that anato- 

 mists began to concentrate their attention upon 

 the study of the development and characteristic 

 functions of organs. Philosophically, this was a 

 long step in advance, but a still longer one was 

 taken at about the same time by that astonishing 

 youth whose career has no parallel in the history 

 of science. When Xavier Bichat died in 1802, in 

 his thirty-first year, he left behind him a treatise 

 on comparative anatomy in which the subject was 



