n CONTENTS. 



CHAPTER III. 



Hbteeostylbd Dimoephio Plants — continued. 



Liaum grandiflorum, long-styled form utterly sterile with own-fonn 

 pollen — Linura perenne, torsion of the pistils in the long-styled 

 form alone — Homostyled species of Linum — Pulmonaria offici- 

 nalis, singular difference in self-fertility between the English 

 and German long-styled plants — Pulmonaria angustifolia shown 

 to be a distinct species, long-styled form completely self-sterile — 

 Polygonum fagopyrum — Various other heterostyled genera — 

 Eubiacese — Mitchella repens, fertility of the flowers in pairs — 

 Houstonia — Faramea, remarkable difference in the pollen-grains 

 of the two forms; torsion of the stamens in the short-styled 

 fona alone ; development not as yet perfect — The heterostyled 

 structure in the several Bubiaceous genera not due to descent in 

 common Page 81-136 



CHAPTER IV. 



Hetekosttled Tkimobphio Plants. 



Lythrum salicaria — ^Description of the three forms — Their power and 

 complex manner of fertilising one another — Eighteen different 

 unions possible — Mid-styled form eminently feminine in nature 

 — Lythrum Grsfferi likewise trimorphic — L. thymifolia dimor- 

 phic — ^L. hyssopifolia homostyled — Nes»a vertioillata trimorphic 

 — Lagerstroemia, nature doubtful — Oxalis, trimorphic species of 

 — 0. Valdiviana — 0. Eegnelli, the illegitimate unions quite 

 barren — 0. speciosa — 0. sensitiva — ^Homostyled species of Oxalis 

 — ^Pontederia, the one monocotyledonous genus known to include 

 heterostyled species 137-187 



CHAPTER V. 



Illegitimate Offspking of Heterostyled Plants. 



Illegitimate offspring from all three forms of Lythrum salicaria — 

 Their dwarfed stature and sterility, some utterly barren, some 



