M. Ulex on Stntvite. 



125 



from 1 # 4> to 1*8 grm. Their primary form is a right rhombic 

 prism. [The admeasurements were made by Prof. Marx.] 



Fig. 1. 



Fig. 4. 



M/ \M 



R 



Fig. 2. 



Fig. 5. 



Fig. 7. 



Fig. 1. Represents a crystal of struvite in its simplest form. 



Fig. 2. The crystal as it most frequently occurs. 



Fig. 4. A segment. 



Figs. 5, 6. Crystals with some secondary planes, but generally only seg- 

 ments occur ; the plane s on both sides large and distinct : the planes 

 h and t very small. 



Fig. 7. A view of the planes collectively as exhibited by some crystals. 



