LECTURE V. 



ADAPTATION OF PLANTS TO THE WORLD. 



Design in plants seen only in organization. Natural selec* 

 tion. Provision made by plants compared with instinct. 

 Wisdom manifested by instinct referred to the Creator. 

 Relation of plants to earth and air. Polarity. 'Structure 

 of leaves. Fall of leaf. Structure of wide-leaved trees. 



Of evergreens. Position of buds.MatJiematical order. 

 Symmetry and welfare of tree secured. Variety of habit. 

 Fitted for m soil. Climate and place in the solar system. 

 Power of the bud. J 'oung fruits. Structure of buds. 

 Food stored up. The potato. Beet and Parsnip. Cen- 

 tury plant. Orchis* Solomon* s-seal. Structure of seed. 



Perfection and variety of machinery. Relation of 

 plants and animals. EjJ'ect of each on the air. Vegetable 

 kingdom subservient to the animal. Its support. Oak 

 galls. Plants respond to the insect's instinct. Fertiliza- 

 tion of plants by insects. SquasJics. Forget-me-nots. 

 Orchids. Results. 



IT is a remark of Paley that design is perhaps less 

 apparent in the vegetable kingdom than in the ani- 

 mal. This may be true, but the argument for design 

 in plants has certainly some advantages. Evidence 

 of design in plants must be sought for exclusively 

 in the structure and function of their organs. There 

 is no mind, no instinct. All changes in them, and all 

 provision which they make for their individual wel- 

 fare, and for their species, must therefore be the 

 result of organization, and not of contrivance origi- 

 nating in thought, inherent in themselves. Where 

 there is a thinking being, it is natural for us to 



