284 
The Giant Ganglion Cells as found in the Adult. 
Paralichthys dentatus. 
The apparatus consists in Paralichthys dentatus, as in the 
other flat-fishes, of a row of very large nerve cells placed in the dorsal 
median fissure, and of the neurites of these cells. These neurites pass 
caudad in the cord forming two symmetrically located fibre-bundles, 
one on each side of the median line. The first giant cell is situated 
in the dorsal median fissure and just behind the union of the restiform 
bodies. This point is between the vagus nerve and first spinal nerve. 
The cell lies imbedded in the connective tissue found in the fissure, 
and its dorsal surface, which rests against the pia-mater, is but 
slightly below the dorsal surface of the cord. It is the first of a single 
row of similar cells which extends from the point just mentioned to 
the 2lst or 22nd spinal segment. They all lie in about the same re- 
lative position in the dorsal fissure, except where one may be crowded 
up or down, or even to one side, by its too numerous neighbors. This 
is most apt to occur in the anterior portion of the row and may be 
so marked, sometimes, as to bring more than one cell at a time into 
a single section. 
The cells are most numerous, in a given length of cord, in the 
anterior portion of the row. Here they are but one half their own 
length apart, but this distance increases and becomes three, four, or 
five lengths in the posterior portion. They show a tendency to become 
grouped in threes. 
There are usually from 400 to 500 of these cells in an adult fish, 
and their numerical distribution may be seen by the following tables 
taken from two adult specimens. In one fish 7'/, cm long and 
weighing 4,8 kilograms there were 452 cells distributed as follows: 
In the Ist to 5th spinal segments were 197 cells 
” ” 6th „ 9th ” 2) ” 1 14 ”„ 
„ ” 10th ” 13th ” „ ” 92 ” 
” ” 14th ” 17th ” ” ”? 38 ” 
” ” 18th ” 21st ’ ” ” 11 „ 
452 
In another large fish, which was presumably older, there were 
385 cells with a similar distribution. 
In size these cells average about 0,10, mm in diameter and there 
is but little variation. Their size is a little larger, perhaps, at the 
anterior portion of the apparatus. Capillaries do not penetrate the 
cytoplasm of these cells as in the giant cells of Lophius. 
