2 The Successive Development Theory. 



reptile class now living in the world. Mammals were added 

 next, until Nature became what she now is, by the addition 

 of Man." — Ibid. p. ccxvi. 



Sir Charles Lyell, in his important Anniversary Address 

 to the Geological Society, February 1851, rejects this theory : 

 before, however, going into detail whether of fact or argu- 

 ment on the question, he makes the following preliminary 

 statement of the principal points which he expects to esta- 

 blish in opposition to the development theory. 



First, in regard to fossil plants, it is natural that those 

 less developed tribes which inhabit salt water, should be the 

 oldest yet known in a fossil state, because the lowest strata 

 which we have hitherto found happen to be marine, although 

 the contemporaneous Silurian land may very probably have 

 been inhabited by plants more highly organized. 



Secondly, the most ancient terrestrial flora with which we 

 can be said to have any real acquaintance (the carboniferous) 

 contains Coniferee, which are by no means of the lowest grade 

 in the phsenogamous class, and, according to many botanists 

 of high authority, Palms, which are as highly organized as 

 any members of the vegetable creation. 



Thirdly, in the secondary formations, from the triassic to 

 the Purbeck inclusive, gymnosperms allied to Zamia and 

 Cycas predominate ; but with these are associated some mo- 

 nocotyledons or endogens, of species inferior to no phsenoga- 

 mous plants in the perfection or complexity of their organs. 



Fourthly, in the strata from the cretaceous to the upper- 

 most tertiary inclusive, all the principal classes of living 

 plants occur, including the dicotyledonous angiosperms of 

 Brongniart. During this vast lapse of time four or five com- 

 plete changes of species took place, yet no step whatever 

 was made in advance at any one of these periods by the addi- 

 tion of more highly organized plants. 



Fifthly, in regard to the animal kingdom, the lowest 

 Silurian strata contain highly developed representatives of 

 the three great divisions of radiata, articulata, and mollusca, 

 shewing that the marine invertebrate animals were as perfect 

 then as in the existing seas. They also comprise some indi- 

 cations of fish, the scarcity of which in a fossil state, as well 



