160 FREDERICK TILNEY AND LUTHER F. WARREN 



millimeters in diameter. It differs from other ganglia only in 

 the fact that the cells are much closer together. Krause ('68) 219 

 described nerve fibers in the epiphyisis having a double contour. 

 Stieda ('69) 376 observed anastomosing processes of cytoplasm 

 with nuclei in a reticulum. Bizzozerp (7 1) 32 found two distinct 

 elements in the organ, namely, stroma consisting of prolongations 

 of the capsule and a definite parenchyma. In this latter were 

 two types of cells. In the larger of these the cytoplasm con- 

 tained granules. He noted that the pineal gland in the new- 

 born and in the infant contains the same elements as in the 

 adult. The only difference is in the fact that the smaller ele- 

 ments have a few branches while the larger cells have none. 

 The cells are arranged in alveoli. Meynert ('77) 271 concluded 

 that the epiphysis was a nerve ganglion. Hagemann (72) 164 

 found two types of epithelial cells, namely, round cells and 

 fusiform cells which are bipolar and multipolar nerve cells. 

 The pineal body, in his opinion, is a combination of epithelial 

 cells and nerve cells. Cruveilhier (77) 73 found in the epiphysis 

 pale, round cells, small nerve cells, large multipolar cells, and 

 calcareous concretions. Mihalkovicz (77) 275 concluded that the 

 pineal cells were not lymphatic corpuscles, but resembled the 

 cells in the lining of the cerebral ventricles. Schwalbe ('8 1) 348 

 considered the pineal cells to be modified epithelium with a 

 striking resemblance to lymphatic corpuscles. Cionini ('85- 

 '86) 66> 67 first demonstrated the presence of neuroglial elements,, 

 the nerve fibers observed belonging to the blood vessels. Dark- 

 schewitsch ('86) 79 refutes the idea that the pineal body is nothing 

 more than a 'simple gland.' By the Weigert method he found 

 the nerve fibers from the following sources: 1) internal capsule, 

 2) striae medullares, 3) Meynert's bundle, 4) optic tract, and 

 5) posterior commissure. Meynert 271 and Pawlowsky 305 have 

 already noted the connection between the posterior commissure 

 and the pineal body. Henle 172B in 1887 considered the pineal 

 body as a lymphatic ganglion. Its parenchyma consisted of 

 two types of cells, i.e., round cells resembling lymph corpuscles 

 and angular cells with many points. 



