1. In the spinal ganglia of the chick of four days the Golgi apparatus or body is in the form of a cluster of granules or rodlets, grouped around the centrosphere, at one side of the nucleus (fig. 1, Pl. 39).
2. In a seven-day chick the Golgi body has increased in size and has begun to spread farther around the nucleus (fig. 3, Pl. 39).
3. All ganglion cells examined, both those of the spinal cord and of ganglia, have the Golgi apparatus in this compacted form during their early stage.
4. At a certain period which varies in the different cells the apparatus spreads out in the cytoplasm (fig. 4, Pl. 39), so that in the adult ganglia the apparatus is more or less scattered throughout the cell (figs. 5, 6, and 7, Pl. 39).
5. It is uncertain to what extent variations in the form of the apparatus, whether reticulate or in the form of individual rodlets, are due to differences in the degree of impregnation with the silver. The plane of the section is also an important factor in determining the appearance presented by the apparatus.
6. The medullary cells of the suprarenal body, which are derived from the central nervous system, have the apparatus in the form of a coiled network or cluster of granules at one pole of the nucleus, similar to the cells of the spinal ganglia at the early stage of development.
7. It is suggested that the scattered form of the Golgi apparatus in adult ganglion cells is an expression of the high degree of metabolism existing in these cells.