202 APPENDIX. 



No. II. 



THE SEED AND SEEDLING. TUBERS: BULBS. 



I. Seed. 



i. Examine a seed of Broad Bean ( Vicia faba) that 

 has been soaked in water. Identify the dark coloured 

 hilum, or point of attachment of the stalk (funicle) of 

 the seed: near its end the position of the radicle and 

 micropyle are easily made out; the latter by squeezing 

 the seed and observing that water is pressed out. Remove 

 the testa from the bean except near the radicle and hilum, 

 and then remove this small remaining piece as a whole, 

 and note, on the inside, the cavity in which the radicle 

 lies; also the micropyle near which the testa gives way 

 during germination. Split the bean and show on your 

 sketch one cotyledon, the radicle, and the plumule. 



ii. Sketch a seed of Cucurbita. The outline of the 

 embryo is indicated on the testa, and will prevent you 

 mistaking for the micropyle a small hole marking the 

 position of the bundles of the stalk of the seed : in soaked 

 seeds this hole is often filled up with pulp. Remove the 

 seed-coat and cut off the broader end of the contents; 

 the remaining part is easily split (from the cut end) into 

 two parts. Show on your sketch 



a. the radicle ; 



6. one cotyledon, showing its veins ; 



c. the plumule, a very small white spot at the base of 

 the cotyledon opposite the radicle. 



