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The only neurite which they ever possess is the one which grows 
ventrad and becomes one of the fibres of those fibre-bundles which lie 
above the central canal and mesad to the dorsal horn. 
These cells were found in all flat-fish examined and their neurites 
have been traced to the bundles in Paralichthys dentatus (see 
Fig. 1) and Pleuronectes americanus. The fibre bundles have 
been seen in all species examined. The dendrites have been seen in 
all species examined, but have been best seen in Pleuronectes 
americanus and Achirus lineatus, in which latter they appar- 
ently anastomose with the dendrites of neighboring giant cells. 
Observations have been made on the structure of the cell, but 
will not be mentioned here, with the exception of the unusual condi- 
ditions found in Pleuronectes americanus with its multinuclear 
cells (see Fig. 2). 
Fig. 4 is a general diagram of the apparatus taken from Pleuro- 
nectes. From the lack of knowledge concerning the exact distribution 
and ending of the neurites of these cells their function cannot be 
stated. But I have assumed an hypo- 
thesis as a working basis until facts shall 
bring out the real meaning and homologies 
of this apparatus. 
In other fishes the distribution of 
neurites from somewhat similar giant cells 
has been described in connection with the 
sensory roots (FRITSCH, ’56, etc.). 
The flat-fish from their bodily position 
and habits have developed the rays of the 
dorsal and anal fins into sense-organs of 
a certain degree of specialization. No one 
can doubt this if the living flat-fish be 
examined and the appearance of the fins 
noted. In Bothus the dorsal fin rays 
are prolonged into a branching mane that 
is carried in front of the head and used 
to touch objects with. 
Fig. 4. Semi-diagrammatic figure of a portion of 
the cord of Pleuronectes containing eleven giant 
cells. : 
I suggest the possible conclusion from these facts that the cells 
are connected with the sense-organs of the dorsal fin, or anal fin, or 
