28 EXPERIMENTAL EVOLUTION LECT. 



minifera, with especial reference to their Variability 

 of Form, illustrated by the Cristellarians " {Monthly 

 Microscopical Journal, 1 876), has worked out the same 

 matter, with the same general result. 



Palaeontology, upon the whole, although yet very 

 fragmentary and incomplete, testifies to the truth of 

 evolution, showing an unmistakable line of descent 

 from ancient types of life to more recent types, and 

 from these more recent types to those which live now. 

 I do not mean to say that in the case of every animal 

 we are enabled to trace its ancestry with exactness 

 to the most remote times, but in many cases this 

 ancestry admits of being very satisfactorily traced, 

 and, with the future progress of geology and palae- 

 ontology, many gaps will be filled up, and many 

 connecting links discovered. 



Among recent books French books well illus- 

 trating the preceding statements, I would recommend 

 those which M. Gaudry, professor of palaeontology in 

 the French Natural History Museum, and one of the 

 leading evolutionists in France, has published, under 

 the significant title of Les Enchainements du Monde 

 Animal dans les Temps Geologiques. These three 

 volumes are entirely devoted to the question of palae- 

 ontological descent, and are most ably written and 

 reasoned. 



Another argument for evolution is derived from 



