PERIPLANETA. 



126. Tracheae. Remove a piec? of the fat-body, mount it in water, and draw it under 

 the high power, showing : tracheae ; fat-cells, containing fat-globules ; fragments of 

 Malpighian tubules. 



127. Nervous System. Remove the alimentary canal, and dissect away the fat- 

 body in order to expose the ventral nerve-cord. Make a drawing to show : cerebral 

 ganglion ; circum-oesophageal commissures ; sub-cssophagcal ganglion ; three thoracic 

 ganglia ; six abdominal ganglia ; ventral nerve-cord. 



