Journal of 



Applied Microscopy. 



Volume I. 



MARCH, 1898. 



Number 3 



Some Methods in the Study of Mature Seeds. 



For some years I have studied the 

 structure of mature seeds, more especi- 

 ally Leguminosae. A few suggestions 

 on methods of procedure may be of some 

 interest to those who wish to use the 

 seeds of these plants to demonstrate cer- 

 tain histological structures. The seeds 

 contain the macrosclerids, the form 

 designated as malpighian, with a con- 

 spicuous cuticle and cuticularized layer. 

 The cuticularized layer is not chemically 



the same as in epidermal cells af Agave. 

 The osteosclerids follow the malpighian 

 and this by the nutrient or pigment 



IFig. 



1— Desmodium dillenil, Darl.— Cross 

 Section of Testa. 



m. — Malpighian cell. 

 m. s.— Malpighian cell, surface view, 

 c— Cuticle. 



c. 1. — Cuticularized layer. 

 1. 1. — Light line, 

 ch. — Chromatopheres. 



c. c— Cell cavity with protoplasmic rem- 

 nants, 

 p.— Pore canals (See surface view.) 

 o.— Ostrosclerid. 

 i.— Intercellular space, 

 n.— Nutrient layer of thin-walled cells, 

 e.— Endosperm aleurone layer, 

 em.— Embryo, 

 q.— Aleurone grains. 

 ■jf.-^Oil globules. 



X 220. (Original.) 



Fig. 2.— Cassia occidentalis L. Cross Sec- 

 tion of Cotyledon. 



n.— Epidermal cell walls, thickened, 

 e.— Epidermal cells, upper surface of 



cotyledon, 

 p. — Palisade parenchyma, 

 g. — Aleurone grains. 

 n.— Nucleus and nucleolus, 

 f.— Oil globules. 



X 220. (Original.) 



layer, then the endosperm with its 

 usually well developed aleurone layer, 

 and in many species, when the endos- 

 perm is conspicuous, thick walled mucil- 

 aginous cells known as the reserve cellu- 

 lose — the embryo with conspicuous pro- 

 tein grains. The above applies well to 

 the seed of honey locust and Kentucky 

 coffee bean. In Phaseolus and Pisum 

 the endosperm is restricted usually to a 

 single layer of aleurone cells and the 

 reserve material is found in the embryo, 

 where it consists of starch, proteid mat- 

 ters, and some fat. 



