Fig. 1. Plan of the central nervous system of Colurostylus . X10. 



Fig. 2 and Fig. 3. Cross sections of the brain, one half shown. X150. 



Fig. 4. Cross section of the first ventral ganglion. XI 50. 



Fig. 5. Cross section of one of the thoracic ganglia. X150. 



Fig. 6. Cross section of one of the upper abdominal ganglia. XI 50. 



Fig. 7. Surface view of one of the thoracic ganglia. XI 50. 



Fig. 8. Surface view of an upper abdominal ganglion. XI 50. 



Fig. 9. Surface view of the last abdominal ganglion. X150. 



