80 



THE INTERNAL STRUCTURE OF MUSCA DOMESTIC A 



cern. 





ac.ms 



Fig. 8. Nervous system. The very fine nerve which runs along the dorsal side of 

 the oesophagus to the proventricular ganglion (Pv.g., fig. 20) has been pur- 

 posely omitted. 



<//;.)). Abdominal nerve, acmn. Accessory mesothoracic dorsal nerve, ac.mt. Acces- 

 sory metathoracic dorsal nen'e. cer.ii. Cervical nerves, c.n. Cephalothoracic 

 nerve cord. O.P. Optic peduncle, pr.cr., Jiis.cr., mt.cr. Pro-, meso-, and meta- 

 thoracic crural nerves, pr.d., ins.d., lut.d. Pro-, meso-, and meta-thoracic 

 dorsal nerves. 



