﻿VIRESCENCE OF OXALIS STRICTA. 



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pluricellular and thin-walled, the other unicellular, with 

 thicker walls covered by numerous wart-like projections. The 

 cells of the epidermal layer of the petal are longer than broad 

 and possess projecting ridges (fig. 1). They are prolonged 

 into blunt papillae. Epidermal cells with smooth walls are 



2. NORMAL PETAL, NEAR BASE, X 400. 



found near the base and especially in the neighbourhood of 

 the vascular bundles (fig. 2). Occasionally a stoma is seen. 

 The interior surface of the petal does not really differ from 

 the exterior surface. 



