. Anatomischer Anzeiger. Anatomy, Comparative; Anatomy, Comparative. 216 Description of Cells. Distribution. —The giant ganglion cells of Ctenolabrus form a single median longitudinal row in the dorsal portion of the cord (Fig. 1). They lie within the dorsal fissure, their upper surfaces being on a level with the dorsal limit of the cord, and are covered by the membrana prima (Fig. 3). Each cell is surrounded by a capsule formed of three parts: 1) the membrana prima, which is arched above each cell (Figs. 3 and 5, mb. pr.); 2) the neuroglia fibres (fbr. n'gl), which come oft from this membrana
. Anatomischer Anzeiger. Anatomy, Comparative; Anatomy, Comparative. 216 Description of Cells. Distribution. —The giant ganglion cells of Ctenolabrus form a single median longitudinal row in the dorsal portion of the cord (Fig. 1). They lie within the dorsal fissure, their upper surfaces being on a level with the dorsal limit of the cord, and are covered by the membrana prima (Fig. 3). Each cell is surrounded by a capsule formed of three parts: 1) the membrana prima, which is arched above each cell (Figs. 3 and 5, mb. pr.); 2) the neuroglia fibres (fbr. n'gl), which come oft from this membrana prima and extend downward to the canalis cen- tralis, and 3) the fine neuroglia network (ret. n'gl). The capsules have an internal diameter of one and a half to two times that of the cell, so that each cell is surrounded by a space, in which it is partly supported by the numerous dendrites which run off from the cell to the surrounding neuroglia. The giant cells extend from the posterior end of the fissura rhom- boidalis caudad through the anterior end of the cord (Fig. 1). The largest cells are near the anterior end of the series, and there is some diminution in size posteriorly. The cells are as a rule more closely set anteriorly, being separated from each other by intervals of from one-fourth to one-half their diameter. The intervals between successive cells increase posteriorly to three and four times the diameter of the cells, the last few cells being irregularly placed at even greater inter- vals (Figs. 1, 2). There is a tendency for the cells to become aggre- gated into groups of three or four cells each. In the an- terior portion of the series mutual crowding may influence the form of the cells, or may result in pushing some of the cells either to one side of the median line, or downward (ventrad) below the level of the others. Occasionally two cells may be found in the same transverse section lying side by side. • Fig. 3. Transverse section of the anterior
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