Aleurone grains are colored yellow with nitric acid and red with Millon's reagent.

The proteid substance of the mass of the grain, of the globoid, and of the crystalloid, reacts differently with different reagents and dyes.

The ground substance and the crystalloids are soluble in dilute alkali, while the globoids are insoluble in dilute alkali.

The ground substance and crystalloids are soluble in sodium phosphate, while the globoids are insoluble in sodium phosphate.

Calcium oxalate is insoluble in alkali and acetic acid, but it dissolves in hydrochloric acid.

Aleurone Grains.

Plate 77a. Aleurone Grains.

1. Curcas {Jatropha curcas, L.).

2. Sunflower seed {Helianthus annuus, L.).

3. Flaxseed (Linum usitatissimum, L.).

4. Bitter almond (Prunus amygdalus, amara, D.C.)

5. Croton-oil seed (Croton tiglium, L.).

6. Sesame seed (Sesamum indicum, L.).

7 and 8. Castor-oil seed (Ricinus communis, L.).