PLATE 13. — Crystals from Animal Secretions. 



Figure 



1. Various prismatic forms of the ammonio-phosphate of magnesia (triple phos- 



phate), naturally formed in human secretions. 



2. Feathery or penniform crystals of the same salt. 



3. Stellate form of the same salt. 



4. Minute imperfectly formed prisms of the same. 



5. Cystic oxide. 



6. Carbonate of lime deposited from water by standing. 



7. Carbonate of lime from the urine of the horse, natural. 



8. Carbonate of lime from the urine of man, natural. 



9. Octahedra of oxalate of lime, as seen in water. 



10. Octahedra of oxalate of lime, as seen when dried. 



11. Ellipsoidal forms of oxalate of lime, natural. 



12. Ellipsoidal constricted, or dumb-bell forms of the same, natural. 



13. Crystals of oxalate of lime, prepared with acid. 



14. Modified octahedra of the same salt, formed by double decomposition. 



15. Crystals of bilifulvine, natural, human. 



16. Crystals of hsematoidine. 



17. Crystals of urea. 



18. Nitrate of urea ; a, b. slowly, c, rapidly formed. 



19. Oxalate of urea. 



20. Uroglaucine. 



21. Cholesterine. 



