53 



GERMINATION OF SEEDS. 



I. Function of life to reproduce itself. 

 II. Environment and activity of a plant directed toward 

 producing seed. 



A SEED. 



I. Outer parts: hilum or scar-point of attachment; mic- 

 ropyle — opening near hilum. Seed-coats; outer 

 — testa ; inner — tegmen. 

 II. Inner parts: cotyledons — thickened leaves in which 

 nourishment is stored, (a) Dicotyledons — two. 

 (b) Monocotyledons — one. 



Plumule — small terminal bud; caulicle or rad- 

 icle — small stem within seed-coats. 

 Embryo: plantlet. 



III. Plant seeds under different conditions. 



1. Light, shade, dark. 



2. Sand, clay, gravel, loam. 



3. Dry, moist, damp. 



4. Hot, warm, cold. 



