232 THE MICROSCOPIST. 



and others more solid, producing a new series of micro- 

 scopic objects after the disappearance of the histological 

 forms (Fig. 183). 



Leucin (Fig. 183, a] forms partly homogeneous drops 

 or globules, partly bodies of concentric layers, and partly 

 stellate spheres of minute crystalline needles. 



Tyrosin (b) generally found along with leucin, forms 

 satiny white needles, isolated, or in sheafs or rosettes. 



iMargarin (c) a mixture and crystalline separation of 

 the solid fats, stearin, and palmitin, occurs quite fre- 

 quently. 



Ammoniaco-magnesian phosphate (d) is only found in 

 alkaline or neutral ichor. 



Pigment-bodies (e) are very small, and have a variety of 

 forms. As characteristic of necrosis the small, black, 

 irregular particles, resisting most reagents, must be dis- 

 tinguished from hsematin pigments, though they are 

 probably identical with melalin. 



Living Organisms (/). In addition to minute fungi, or 

 moulds (aspergillus, oidium, etc.), vibriones are quite com- 

 mon. Pasteur regards them as the visible elements of 

 decay (see page 135). 



DEGENERATION OF TISSUES. 



Degenerations are usually divided into two classes, true 

 degenerations, or metamorphoses, and the infiltrations. 



1. The true degenerations or metamorphoses are char- 

 acterized by the direct change of the albuminoid constitu- 

 ents of the tissues into new material. The metamor- 

 phoses include fatty, mucoid, and colloid degenerations. 



2. The infiltrations differ from the true degenerations, 

 since the new material which exists in the tissues is not 

 derived from their albuminoid constituents, but is de- 

 posited in them from the blood. The anatomical char- 

 acters are much less altered than in the metamorphoses, 



