THE PINEAL BODY 



167 



Krabbe ('II) 217 studied one hundred human pineal bodies, 

 both male and female, from birth to seven years of age and from 

 fourteen years to ninety-two years. There was a gap in his 

 subjects between the ages of seven and fourteen years. He 

 found two types of cells in the epiphysis: 1) special pineal cells 

 and 2) neuroglia cells. He thinks the granules in the cells leave 

 the protoplasm, traverse the intercellular space to enter the 

 blood, lymph, or cerebrospinal fluid, Krabbe does not agree 

 with Dimitrova 92 that the fundamental element of the pineal 



Fig. 81 Cells with granular protoplasm in the pineal body of Bos taurus (Wei- 

 gert's method), according to Dimitrova, 1901. 



body is neuroglia, for he considers her criteria in distinguishing; 

 neuroglia insufficient. He himself never observed muscle fibers 

 in any of the forms which he has studied. Krabbe concludes 

 that the epiphysis in man shows certain signs of in volution ,. 

 as, for example, concretions, hyperplasia of connective tissue,, 

 neuroglial plaques with cysts, and the presence of cells in a state 

 of disintegration. The involution begins at seven years of 

 age, but even in the adult the pineal body shows signs of active 

 function. The secretory process is manifest in the following 



