792 THE URINE. 



Any of the above-named fibers may be found dyed in differ- 

 ent colors. 



Feather appears in single barbules, or in the shape of branch- 

 ing formations ; the ends of the barbules are whip-like, the size 

 of the links gradually decreasing toward the terminations. Scales 

 from the wings of insects are also found ; these are delicate, ser- 

 rated plates, with a stem-like projection. 



Of vegetable matters the most common are oi'dium and myce- 

 lium of mildew, bits of cork, charcoal particles, pollen of plants r 

 mostly the seed of lycopodium (globular formations with a dis- 

 tinct shell, studded with thorny projections), and particles of 

 wood. Starch-granules are very common in female urine, being 

 used for powdering the genitals. In acid urine, motionless lep- 

 tothrix and bacteria are found; in alkaline urine, micrococci r 

 bacteria, and leptothrix in active motion. 



It must be known that flaws, which often present the shape of butterflies 7 

 wings, scratches of the covering-glass, rust-particles in both the cover and 

 the slide, often occur. A physician brought me a specimen of a worm-shaped 

 mass of rust in the cover, which he mistook for an unknown parasite. He 

 claimed having seen the parasite quite often, and I discovered that he had 

 used the same cover for examination of the urine of a patient. 



Crystalline Sediments. The crystalline formations found in 

 urine belong either to the group of acids and acid-salts, or to the 

 groups of alkaline salts. The acid sediments are uric acid, oxalate 

 of lime, urate of soda (amorphous), and hippuric acid. The first 

 three are very common sediments, while hippuric acid is rare. 

 Still rarer are cystine and tyrosine, which also belong to this 

 group. The alkaline sediments are urate of ammonia, triple phos- 

 phates, calcium phosphates (which appear both as amorphous and 

 crystalline sediment), and calcium carbonate (amorphous and 

 crystalline). Magnesium phosphate is exceptional. 



(1) Uric acid is a constant ingredient of the urine of carniv- 

 ora. Its amount is greatly augmented by rich animal and veg- 

 etable food, by acute febrile diseases, by impeded function of the 

 heart, the lungs, the kidneys, the diaphragm, etc. It is decreased 

 in profuse secretion of urine, and in the later stages of nephritis, 

 when the secretion of all salts is interfered with. It is also 

 increased by bodily exercise. Its amount varies greatly at differ- 

 ent times in the urine of the same person. 



Uric acid appears in lozenge-shape (rhomboidal prisms), with 

 numerous variations, and has alwaysa brown or red-brown color, 



