8 Botanical Microfechnique 



Fig. 2.1— Methods of siilxiiN idiiif; lc;i\fs for cmbcddint;: ./ /). loiij^ iiairou leaves 

 and iraiisvcMsc i)icccs icmovcd from siuli lca\cs: /•,". cniljccklcd piece of leaf fastened 

 to mounting block; /•'-//, laij^e Ijioad leaf and excised pieces of l)lade and petiole: 

 /, portion of leaf with fungus pustules: /. enlarged \ie\\ of excised aeci;i: A. em- 

 bedded piece of leaf beating aecia. fastened to mounting block. 



cells contain ingredients tiiat are toxic to proioplasni. In oidei to 

 MO)) lile |)rocesses (jtiickK and wiiliotit distortion ot structtirc, the 

 killing fltiid nnist icacli the iinuiiiiosi (clls ol a \)'iv(.v ol tissue belore 

 disintegration takes place. Most reagents penetrate very slowly 

 through the cuticle or cork on the surfaces ol plant organs, btit 

 j)enctraiion is nuuh more raj)id tlnough cm siirlaces. Therefore, 



