CONTENTS. sxiii 



fertile Oxalis, transmission of form to the legitimate and 

 illegitimate seedlings Primula Sinensis, illegitimate offspring 

 in some degree dwarfed and infertile Equal-styled varieties 

 of P. Sinensis, auricula, farinosa, and elatior P. vulgaris, 

 red-flowered variety, illegitimate seedlings sterile P. veris, 

 illegitimate plants raised during several successive genera- 

 tions, their dwarfed stature and sterility Equal-styled varie- 

 ties of P. veris Transmission of form by Pulmonaria and 

 Polygonum Concluding remarks Close parallelism between 

 illegitimate fertilisation and hybridism . . Page 188-244 



CHAPTER VI, 



CONCLUDING REMARKS ON HETEROSTYLED PLANTS. 



The essential character of heterostyled plants ^Summary of the 

 differences in fertility between legitimately and illegitimately 

 fertilised plants Diameter of the pollen-grains, size of an- 

 thers and structure of stigma in the different forms Affinities 

 of the genera which include heterostyled species Nature of 

 the advantages derived from heterostylism The means by 

 which plants become heterostyled Transmission of form 

 Equal-styled varieties of heterostyled plants Final re- 

 marks . . 245-277 



CHAPTER VII. 



POLYGAMOUS, DICECIOUS, AND GYNO-DICECIOUS PLANTS. 



The conversion in various ways of hermaphrodite into dioecious 

 plants Heterostyled plants rendered dioecious Rubiaceae 

 Verbenaceae Polygamous and sub-dioecious plants Euo- 

 nymus Fragaria The two sub-forms of both sexes of Rham- 

 nus and Epigtea Ilex Gyno-dicecious plants Thymus, dif- 

 ference in fertility of the hermaphrodite and female individuals 

 Satureia Manner in which the two forms probably origi- 

 nated Scabiosa and other gyno-dio3cious plants Difference in 

 the size of the corolla in the forms of polygamous, dioecious, 

 and gyno-dioecious plants 278-308 



