PLATE 86 



SOLITARY CRYSTALS 



1. Quassia (Picrana excelsa [Swartz.], Lindl.). 



2. Uva-ursi leaf (Arctostaphylos uva-ursi [L.], Spring.). 



3. Quebracho bark (Aspidosperma quebracho-bianco, Schlechtendal). 



4. Wild-cherry bark (Prunus serotina, Ehrh.). 



