350 LINN^US AND THE JUSSIEUS 



that inquiry into the sexual economy of the flower 

 which has since been pursued with such remarkable 

 success by Darwin and Hermann Mtiller. In the early 

 nineteenth century microscopes, far better and more 

 convenient than any which Malpighi or Swammerdam 

 could command, made it possible to examine in detail 

 the internal changes which constitute the process of 

 fertilisation, and to follow the growth of the most 

 delicate embryonic tissues/ We are now fortunate 

 enough to possess something that really deserves to be 

 called a morphology and physiology of the flower, based 

 upon elaborate investigations, not only of a multitude 

 of flowering plants, but of the principal types of the 

 higher cryptogams as well. Even the remote history of 

 the flowering plant, which long seemed to be unsearch- 

 able, has been illustrated by the close study of coal- 

 measure fossils, and with such eflect that the descent of 

 the flowering plant from cryptogamic ancestors, which 

 had been inferred from facts of recent structure, can be 

 verified at some points by the production of long-extinct 

 transitional forms. ^ These vast extensions of knowledge, 

 which cause modern botany to differ so conspicuously 

 from the botany known to the ancients or the revivers 

 of science, may be said to take origin from the experi- 

 ments of Camerarius. Then and not till then was it 

 definitely proved that stamen and pistil co-operate to 

 produce the embryo, and a clear reason could at last be 

 given for the long-familiar fact that the fruit is in all 

 higher plants preceded by a flower. What the supposed 

 flowers and fruits of ferns, mosses and seaweeds might 

 be, and whether cryptogams really produce anything 



1 Amioi in 1823 observed the pollen-tube emitted from the pollen-grain ; 

 in 1830 he discovered its entry into the mioropyle. 



2 Oliver and Soott, Phil. Trans., 1904. 



