596 THE SENSES AND SENSORY ORGANS. 
Primitive Chordotonal Organs are typically represented in many 
larve, asin Tabanus, most species of Chironomus, and Syrphus. 
They appear as cords, connected at two points with the integu- 
ment, like a stretched string, the chordotonal ligament. The 
chordotonal ligament is connected with the terminal ganglion 
of a nerve, about midway between its ends (Fig. 74, B). 
The chordotonal ligament is a fibrous band connecting the 
nerve ganglion with the integument, and is probably a modifica- 
tion of the nerve-sheath. It encloses a peripheral nerve-cell, or 
a group of cells, and one or more remarkable spindle-like quasi- 
chitinous elements, the auditory rods (Haarstifte). Graber 
restricts the term ligament to the non-nervous proximal part of 
the chordotonal organ, and terms the distal part the terminal 
nerve string ; but it appears to me that the connective nerve- 
sheath extends in both directions as a ligament, and, for con- 
venience of description, I have used the term for the whole of 
the stretched cord which encloses the nerve terminals. Each 
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