0000000000273633
AUTHOR
K. Behrend
The musculature of the electric fish Eigenmannia virescens (South American green knife fish) characterized with cytochrome oxidase staining
Using cytochrome C-oxidase staining, different types of somatic musculature were clearly distinguished in the gymnotoid fish Eigenmannia virescens. Except for a few thin fibres in the region of the horizontal septum, which stained faintly, no others in the trunk muscle stained. Strong staining appeared in the fibres of the anal fin muscles. According to the classification of fish musculature into white, intermediate and red, only the locomotory organ of this fish has red fibres, whereas the trunk muscles are white. The red muscles along the horizontal septum, found in all other fish which have been investigated in this respect, seem to be absent. This is noteworthy since the anal fin alone …
How a Fish’s Brain May Move a Fish’s Body
The brainstem of the electric fish Eigenmannia virescens contains a small number of neural networks projecting directly onto the motoneuron pools of the spinal cord such that each segment is reached by at least one neuron of all the networks. Quantitative data of movement patterns, recorded from freely moving animals as well as elicited by electrical stimulation of the single networks, suggest that each network contains a full program for a particular movement, e. g. bending of the body axis to one side. By virtue of the structural relationship the programs are executable with a small number of segments. Mixing of small pieces of programs along the body axis allows for a far larger variety …
Descending Connections from the Brainstem to the Spinal Cord in the Electric Fish <i>Eigenmannia</i>
The descending connections from the brainstem to the spinal cord in Eigenmannia sp. were demonstrated using the horseradish peroxidase (HRP) technique. The spinal cord was transecte