Pammel — Anatomical Characters of Seeds of Leguminosae. 141 



The inner colors blue more rapidly. Protein grains are 

 abundant in cavity. The lower portion of the endosperm 

 consists of elongated, thick-walled cells ; this layer surrounds 

 the whole embryo. 



Embryo. First row of cells much smaller than those 

 within, nearly isodiametric, outer walls thickened ; the lateral 

 thin-walled, apparently striated, with longitudinal bars. Sev- 

 eral rows of palisade cells on superior face of cotyledon. Cells 

 packed with fat and protein grains. Walls color blue with 

 chlor-iodide of zinc. Starch is absent. 



Laburnum, L. 



Laburnum anagyroides. Medic. 



For allied species see Cytisus scoparius. — PL X. f. 3. 



According to Nadelmann the structure of Cytisus Laburnum 

 approaches that of Teiragonolobus purpureus. The Malpi- 

 ghian cells carry a green pigment ; the endosperm reaches its 

 greatest development laterally. The tertiary membrane of 

 the reserve cellulose in the endosperm colors blue. The seeds 

 of Scotch Broom were formerly considered medicinal. Huse- 

 mann and Marme isolated a very poisonous, strongly basic 

 alkaloid, cytisin. 



Testa and endosperm measure 431.6 /i in thickness, the endo- 

 sperm being more than twice as thick as the testa. The testa 

 differs little from that of Genista tinctoria, 



Malpighian. Cuticle forms a continuous layer and in 

 mounted specimens shows fissures ; light line is a narrow zone 

 close under the cuticle. Cell-cavity wide at lower end, grad- 

 ually tapering upward. Canals extend down into the cell-wall 

 for more than one-third of the distance. 



Nutrient. This layer is moderately developed, consisting 

 of four rows of irregular, thin-walled cells, containing some 

 protein grains. 



Endosperm. The first layer of cells, the aleurone, with 

 thick walls, containing protein grains and fat; the remainder 

 of the endosperm, except the portion next to the embryo, 

 consists of thick-walled cells with pore-canals; these contain 

 some fat and protein grains. 



