PLATE 85 



Solitary Crystals 



1. India senna (Cassia angustifolia, Vahl.). 



2. Cascara sagrada bark (Rhamnus purshiana, D. C). 



3. Frangula bark (Rhamnus f ran gula, L.). 



4. White pine bark (Pinus strobus, L.). 



5. Tamarac bark (Larix laricina [Du Roi], Koch). 



