Cerebellum in Cases of "Shock." 



77 



everything was ready the dog was quickly overcome with either 

 chloroform or ether. 



As soon as the anesthesia was complete the thorax was opened 

 rapidly and a canula introduced into the descending aorta, pointing 

 upward. The right side of the heart was then opened and two 

 liters of Ringer's solution were allowed to flow through the canula. 

 After the Ringer's solution fixation was secured either by Zenker's 

 fluid or by 10 percent, formaldehyde solution. Follownig this the 

 brain was at once removed and placed in Zenker's fluid or 10 

 per cent, formaldehyde, corresponding to the fixative used for per- 

 fusion. 



Tissue was mounted both in celloidin and paraffine and stained 

 by many methods. This report is based on the following methods : 

 Eosin-Unna's alkaline methylene blue, the carbol-thionin, Mal- 

 lory's aniline blue and the hemalum-acid fuchsin. In most 

 cases blocks of tissue were cut so that the Purkinje cell might be 

 studied in three planes. 



In describing the following types of Purkinje cells it were well 

 to call attention to some characteristics common to all and also 

 to accentuate the fact that I do not claim that these types represent 

 essentially different entities. This may be so, or on the other 

 hand the different types may represent different stages in meta- 

 bolic activity of a single entity. 



Characteristics Common to All Types of Purkinje Cells. 



1. The nucleus is usually oval and its long axis does not neces- 

 sarily correspond to the long axis of the perikaryon. 



2. Excentric placing of the nucleus is found frequently in cells 

 which we must accept as normal. 



3. The nuclear cap is a condensation of tigroid material in the 

 form of a crescent which is applied so closely to the nucleus that at 

 times it is difficult to say whether the substance be intra or extra- 

 nuclear. The periphery of the cap is smooth in the majority of 

 cases. But occasionally a lumpy or torn appearance is found in 

 which event ragged masses of the cap project into the cytoplasm. 

 The nuclear cap stains intensely with the basic dies. 



4. The periphery of the nucleus is not necessarily an unbroken 

 oval or circle. In conditions which we must accept as normal 



