INTRODUCTORY LESSONS. Vii 
5. Albuminous Seeds, Remove the shell-like coat of a castor bean, 
and carefully split it flatwise. What at first seems to be a large plumule 
proves to be free from the rest of the kernel, and with care you may be 
9. Seed of Willow or Dig- 
ger Pine cut so as toshow 
the straight embryo in the 
center of the oily albumen. 
a and b, embryo taken out, 
the cotyledons (6) separated. 
10. Seed of the Castor-bean. 
a, the broad thin embryo 
neatly dividing the albu- 
men; b, the embryo removed 
and the leaf-like cotyledons 
10 separated, 1]. Seed of Da- 
tura (Brugmaneia’, showing atu the bent embryo in the scanty albumen; b, the embryo taken out and 
the slender cotyledons separated. 12. A grain of coffee. a, the straight embryo. 
able to get it out whole (Fig. 10.) Itisa straight embryo with beautifully 
veined, leaf-like cotyledons, embedded in a white, oily substance, which 
makes up the mass of the kernel. This substance is called Albumen, a 
name which applies to anything inclosed with the embryo by the seed 
coats. Peas, beans, acorns, nuts, and most large seeds have no albumen. 
Carefully cut thin slices from a well soaked coffee grain until its embryo 
appears as represented in Fig. 12. The horny, folded albumen makes 
up most of the seed. A similar, but smaller embryo, may be found in 
the brain-shaped, fleshy albumen of the ivy seed. The ee of the 
Tree-Datura, or Stramonium, is shown in Fig. 11. 
It has slender cotyledons, folded down against a 
thick radicle, the whole embedded in tough, fleshy 
albumen. Take the embryo of a Morning-Glory 
seed and pick the bits of transparent, jelly-like 
albumen out of the pockets in the crumpled coty- 
ledons. An attempt to flatten out the cotyledons 
will probably result in something like b, Fig. 13, 
which may lead you to suppose that the coty- 
13. 
Morning - Glory 
ledons are separately crumpled, which is not the 
case. They stick closely together by their inner 
faces, as do the cotyledons of other seeds you have 
examined, and they are crumpled as one; but, being 
notched at the end, they readily split down the 
center. 
Buckwheat seeds will give you some trouble. 
just appearing above the 
ground with the seed coat 
sticking to the cotyle- 
dons. a, the swollen 
seed; b, embryo, with 
the crumpled cotyle- 
dons split down the 
middle in the attempt 
to flatten them. 
Indeed, it will 
