86 
PHARMACEUTICAL BOTANY 
These crystals are classified according to form and belong either to 
the monoclinic or tetragonal system (See Fig. 38). 
A 
A A 
V 
A 
* * 
E 
Fig. 38.—Various forms of calcium oxalate crystals. A, styloids from the 
bark of Quillaja saponaria; B, rosette aggregate from rhizome of Rheum officinale; 
C, raphide from the bulb of Urginea maritime; D, crystal fiber as seen in longi¬ 
tudinal section in either the xylem or phloem regions of Glycyrrhiza; E, micro¬ 
crystals (crystal sand) isolated from the parenchyma of Belladonna root; F, 
monoclinic prisms; and G, twin-crystals from leaves of Hyoscyamus niger. All 
highly magnified. 
Crystals belonging to the Mono clinic System and Examples of Drugs 
Containing them: 
1. Solitary—Hyoscyamus, Acer Spicatum, Viburnum Prunifolium. 
2. Rosette Aggregates—-Althaea, Gossypii Cortex, Stramonium, 
Granatum, Rheum, Fceniculum, Viburnum. 
3. Columnar (Styloids)—Quillaja. 
