314 THE MICROSCOPIST. 



angle being next the eye (Plate XXVII, Fig. 249). 

 Dumb-bell forms and circular 'or oval crystalline masses 

 are sometimes seen. 



Oxalate of lime is found as a urinary deposit in various 

 conditions, as in pulmonary and dyspeptic affections. It 

 is usually associated with hypochondriasis, and in cases 

 of overfatigue, particularly from mental work, it is com- 

 mon. The train of nervous and dyspeptic symptoms with 

 which it is associated have been supposed to indicate an 

 "oxalic acid diathesis," and have been named "oxaluria." 

 Its association with calculi renders it interesting to the 

 surgeon. 



Chloride of sodium never crystallizes from fluid urine. 

 On evaporation it occurs in stellar form or in cubes (Plate 

 XXVII, Fig. 250). The presence of urea sometimes dis- 

 poses it to assume the form of a regular octahedron. The 

 amount of this excretion in typhoid fever and in inflam- 

 mations of the respiratory organs is greatly diminished. 

 It is absent in commencing hepatization of the lung, but 

 returns on resolution of the inflammation (see Chlorides, 

 page 302). 



Cystin crystallizes in characteristic six-sided plates 

 (Plate XXVII, Fig. 251). It contains twenty-six per 

 cent, of sulphur, and is considered a product of decompo- 

 sition. It is often associated with calculus. Some regard 

 it as indicating a strurnous and ill-nourished system. 



Carbonate of lime occurs rarely in human urine, but is 

 common in that of the horse. Its form is that of a 

 spherule made up of acicular crystals. It effervesces in 

 acetic acid. 



Tyrosin, in sheaflike or globular masses, sometimes 

 occurs in typhus and in atrophy of the liver. 



III. PUS AND MUCUS IN DIAGNOSIS. 



"We have already considered the bioplasts of pus and 

 mucus as identical in character with other leucocytes, as 



