i2o PROGRESS OF SCIENCE. 



1802 57. D'Orbigny studied and classified the FORA- 

 MINIFERA a most important class, since the accumulation 

 of its remains constitutes geological strata. 



1804 92. Owen is the highest authority in many im- 

 portant branches of comparative anatomy through his studies 

 of the GREAT APES, the KANGAROOS, the giant New Zealand 

 Wingless Birds (the DiNORNis), the CEPHALOPODS, the 

 BRACHIOPODS, etc. ; his anatomical labours are so numerous 

 and important that he may be called the greatest comparative 

 anatomist of his time. He introduced the study of palaeon- 

 tology in England, and no scientist since Cuvier, whose pupil 

 he was for a time, has enriched palaeontology to a greater 

 extent than he has. He contributed a vast series of papers 

 on extinct animals and their living representatives, making 

 discoveries which filled up the gaps in past and present 

 species. He was the first fully to describe the GREAT SLOTHS 

 (the Megatherium 18 feet long, the Mylodon n feet), 

 armadilloes, and SAURIANS of South America, the flying 

 reptiles, the swimming lizards and tortoises of the Secondary 

 and Tertiary periods, and to bring into notice countless 

 reptiles, birds, and mammals in British strata. But his 

 investigations of the saurians (so-called antediluvian reptiles), 

 first of those known to Cuvier, and next, of the Cetiosaur, 

 the Megalosaur, the Scelidosaur, and then the Mylodon, and 

 then the Dinornis, may be pronounced his most original and 

 fascinating work. He carried our knowledge about these (so- 

 called) antediluvian animals very far indeed, and by his 

 luminous views left very few anatomical problems concerning 

 them to be solved, though it was reserved to the next generation, 

 as our next notice will show, to give an extension to the science 

 of life in early geological periods undreamt-of in Owen's 

 prime time. Like Cuvier, he applied the law of correlation 

 of structure, and could, with a bone, a vertebra, or a tooth, 

 reconstruct the extinct animal of which it had been a part. 

 By his palaeontological researches and discoveries, he caused 

 geology to obtain still greater popular favour than it had 

 obtained before thereby powerfully assisting the work of 

 William Smith, Sedgwick, Murchison, Lyell, and Agassiz. 

 He believed, with Sedgwick, in the separate origin of distinct 



