118 SEEDS. 



(60) Cevadilla Seeds. 



*- . 



/"ti; 



The seeds of Schcenocaulon officinal;' A. Gray (N.O. 

 Liliacese). 



The seed-coats comprise three distinct layers, all of which are 

 brown in colour. 



The outermost layer (te) is composed of a single row of radi- 

 ally elongated cells, the outer walls of which are considerably 

 thickened. In surface view these cells are polygonal, and their 

 walls are straight or slightly wavy, and deep brown in colour. 



The middle layer (tm) is formed of several rows of rounded or 

 polygonal cells with small intercellular spaces and incon- 

 spicuous pits ; they are also coloured brown, bat less deeply 

 than the cells of the outermost layer. 



The innermost layer (ti) consists of a single layer of elongated 

 cells, with thin, pitted walls. 



The cells of the endosperm (alb) are polygonal and isodia- 

 metric; the walls are colourless, very thick, and very con- 

 spicuously pitted. They contain a granular, nitrogenous 

 substance and fixed oil. 



In the powdered seeds, vessels (tr) and fibres (/) from the raphe 

 are to be found. 



The diagnostic characters of powdered cevadilla seeds are: 



(a) The brown, elongated polygonal cells of the epidermis 



(b) The cells of the endosperm ivith pitted or irregularly 

 thickened walls. 



