McCracken, Egg-laying Apparatus of Silkworm. 285 



inal ganglion is much more limited in the decapitated or dethor- 

 axed insect than in the normal insect. Repetition of stimulation 

 causes repeated responses with no evidence of fatigue or decrease 

 of functional activity until death ensues. There is neither awk- 

 wardness nor feebleness exhibited, neither is there evidence of aug- 

 mentation. 



7. Response of the ovipositor is initial and endures after all 

 eggs have been oviposited, therefore entirely independent of the 

 rest of the reproductive apparatus. 



8. The posterior abdominal ganglion is the controlling center 

 of the reproductive mechanism and exhibits a high degree of 

 independent activity. 



9. The reflexes of movement connected with the three anterior 

 abdominal and the thoracic ganglia are coordinate with the reflexes 

 of the ovipositing apparatus connected with the posterior abdom- 

 inal ganglion. 



In conclusion, it is apparent that while an intact nervous system 

 is necessary for a prompt, efficient and continuous functioning of 

 the reproductive system, in the absence of the head or head and 

 thoracic ganglia, external stimulus brings about prompt, efllicient 

 and complete though not continuous reaction. In the absence of 

 head or head and thorax, there is no apparent augmentation of the 

 reflexes. This reaction is efficient if the posterior abdominal 

 ganglion alone is intact. Corresponding ganglia in the anterior 

 abdominal segments are not only reflex centers but centers of cor- 

 relation as well. 



