The Seed and its Germination 
497 
form of definite grains, which in the simplest cases show no 
structure. In the lupin (fig. 12) and other leguminous plants 
they are embedded in a matrix of protoplasm, from which by 
certain solvents they can be separated, leaving a coarse net- 
work of protoplasm behind (fig. 13). In other cases, as in the 
seed of the castor-oil plant, the grains of proteid are very 
Fig. 12. Fig. 13. 
Two Cells from Cotyledon of Lupin. 
(12) with unaltered aleurone grains, «; (13) after treatment with sulphuric acid. This has 
dissolved the aleurone grains, and has left the protoplasmic network visible, b, drops of oil. 
Fig. 14. — Tliree Cells from Endosperm ' Fig. 15. — Two Cells fromCotijledon, 
of Castor-oil Seed. of Pea. 
a, aleurone grains, containing, 6, crystalloid a, cell-wall; b, starch grains ; c, aleurone 
and, c, globoid; d, meshwork of protoplasm. grains. 
complex (fig. 14), consisting of an ovoid mass of granular 
appearance, in which are embedded a crystal-like body with 
well-defined edges, and an aggregation of mineral matter, chiefly 
a double phosphate of calcium and magnesium. These masses 
of proteid matter are generally spoken of aa aleurone grains. In 
