308 STUDIES IN THE EVOLUTION OF ANIMALS 



upper and lower chalk, the Cycads, which previously were very 

 abundant, now become less and less, and higher groups of plants, 

 all highly specialised, take their places. 



In this connection Sir J. William Dawson 1 says : ' We have a 

 great and sudden inswarming of the higher plants of modern types 

 at the close of the lower Cretaceous. In relation to this, Saporta, 

 one of the most enthusiastic of evolutionists, is struck by this 

 phenomenon of the sudden appearance of so many forms, and 

 some of them the most highly differentiated of dicotyledonous 

 plants. The early stages of their evolution may, he thinks, have 

 been obscure and as yet unobserved, or they may have taken place 

 in some separate region, or mother-country as yet undiscovered, or 

 they may have been produced by a rapid and unusual multiplica- 

 tion of flower-hunting insects ! or it is even conceivable that the 

 apparently sudden elevation of plants may have been due to 

 causes still unknown. This last seems, indeed, the only certain 

 inference in the case, since, as Saporta proceeds to say in 

 conclusion : " Whatever hypothesis one may prefer, the fact of the 

 rapid multiplication of dicotyledons, and of their simultaneous 

 appearance in a great number of places in the Northern Hemi- 

 sphere at the beginning of the Cenomanian Epoch, cannot be 

 disputed." ' 



Quoting from Dr. Newberry, 2 Sir J. W. Dawson at p. 205 says : 

 ' But the most surprising discovery yet made is that of a number 

 of quite large helianthoid flowers, which I have called Palceanthus! 

 It seems probable that the composite formed a part of the 

 Cretaceous Flora. Dr. Newberry adds : * No composite flowers 

 have before been found in the fossil state, and as these are among 

 the most complex and specialised forms of florescence, it has been 



1 Geological History of Plants, p. 193. 



2 B^illetin of the Torrey Botanical Clttb, March 1886. 



