400 THE PINEAL ORGAN 



activity, and she believed that the nucleus produces a substance the 

 chemical composition of which is unknown and which is periodically 

 discharged into the cytoplasm. The spherules were stated to approach 

 the nuclear membrane, pass through this into the cytoplasm, and after- 

 wards disappear. The nuclear membrane was then said to be regenerated. 

 Similar appearances have been described by other authors, e.g. Krabbe, 

 who reported the presence of the nuclear spherules in the human subject 

 commencing about the eighth year, reaching a maximum during the 

 fourteenth year, and persisting in old age. Uemura and Weinberg have 

 seen the spherules in the pineal body of a child of 4 years and under 

 3 years of age. The secretory nature of the nuclear spherules has, how- 

 ever, been doubted by many authors, more particularly by Achucarro 

 and Sacristan, Biondi, Josephy, and Walter. Intranuclear granules and 

 spherules, wrinkling, outpocketing, and inpocketing of the nuclear 

 membrane are quite common occurrences in cells with large nuclei in 

 many structures besides the pineal body. Moreover, the small recesses 

 between the folds of a wrinkled nuclear membrane may enclose granules 

 of protoplasm which stain with hematoxylin and the various stains men- 

 tioned above in a similar way to the spherules of the parenchyma cells. 

 Nevertheless the abundant granules which were demonstrated by Hortega 

 within the nucleus in the cell-body and around the parenchyma cells by 

 means of his silver carbonate method, in the pineal body of the ox, sheep, 

 and human subject, must be regarded as histological evidence of a granular 

 deposit of some stainable substance differing in its chemical composition 

 from that of the unmodified nucleus and cell-body. Whether the chemical 

 changes indicated by the presence of these granules is evidence of an 

 internal secretion seems as yet to be indecisive, and more particularly is 

 this the case since, as far as we are aware, the presence of the granules 

 has not been noted in the capillary vessels. 



The Supporting Tissues of the Pineal Organ 



In our general description we have already alluded to the fibrous 

 connective tissue elements comprising the capsule, the trabecular, and 

 the delicate intercellular connective tissue derived from the sheaths of 

 the intralobular vessels. Besides the ordinary connective tissue, there 

 are occasionally seen the branched microglial elements which have been 

 described in connection with the central nervous system ; these are some- 

 times present in plaques of glial tissue, and more especially in certain 

 pathological states. The microglial elements probably enter the tissue 

 of the pineal body in the same way as they pass into the central nervous 

 system, namely, as independent units which are first seen beneath the 



